INTERNATIONAL CODE OF BOTANICAL NOMENCLATURE
 
 

                                         PREAMBLE

1.  Botany requires a precise and simple system of nomenclature used by
botanists in all countries, dealing on the one hand with the terms which
denote the ranks of taxonomic groups or units, and on the other hand with
the scientific names which are applied to the individual taxonomic groups
of plants ¹. The purpose of giving a name to a taxonomic group is not to
indicate its characters or history, but to supply a means of referring to it
and to indicate its taxonomic rank. This Code aims at the provision of a
stable method of naming taxonomic groups, avoiding and rejecting the use
of names which may cause error or ambiguity or throw science into con-
fusion. Next in importance is the avoidance of the useless creation of
names. Other considerations, such as absolute grammatical correctness,
regularity or euphony of names, more or less prevailing custom, regard for
persons, etc., notwithstanding their undeniable importance, are relatively
accessory.

2.  The Principles form the basis of the system of botanical nomenclature.

3.  The detailed Provisions are divided into Rules, set out in the Articles,
and Recommendations. Examples (Ex.) are added to the rules and recom-
mendations to illustrate them.

4.  The object of the Rules is to put the nomenclature of the past into order
and to provide for that of the future; names contrary to a rule cannot be
maintained.

5.  The Recommendations deal with subsidiary points, their object being
to bring about greater uniformity and clarity, especially in future nomen-
clature; names contrary to a recommendation cannot, on that account, be
rejected, but they are not examples to be followed.

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¹ In this Code, unless otherwise indicated, the word “plant” means any organism tradition-
  ally studied by botanists (see Pre. 7).

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6.  The provisions regulating the governance of this Code form its last
division.

7.  The rules and recommendations apply to all organisms traditionally
treated as plants, whether fossil or non-fossil ¹, e.g., blue-green algae (Cy-
anobacteria) ² ; fungi, including chytrids, oomycetes, and slime moulds;
photosynthetic protists and taxonomically related non-photosynthetic
groups. Provisions for the names of hybrids appear in App. I.

8.  The International code of nomenclature for cultivated plants is pre-
pared under the authority of the International Commission for the Nomen-
clature of Cultivated Plants and deals with the use and formation of names
for special plant categories in agricultural, forestry, and horticultural no-
menclature.

9.  The only proper reasons for changing a name are either a more pro-
found knowledge of the facts resulting from adequate taxonomic study or
the necessity of giving up a nomenclature that is contrary to the rules.

10.  In the absence of a relevant rule or where the consequences of rules
are doubtful, established custom is followed.

11.  This edition of the Code supersedes all previous editions.

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¹ In this Code, the term “fossil” is applied to a taxon when its name is based on a fossil
  type and the term “non-fossil” is applied to a taxon when its name is based on a non-
  fossil type (see Art. 13.3).

² For the nomenclature of other prokaryote groups, see the International code of nomen-
  clature of bacteria.

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DIVISION I. PRINCIPLES

Principle I

Botanical nomenclature is independent of zoological and bacteriological
nomenclature. The Code applies equally to names of taxonomic groups
treated as plants whether or not these groups were originally so treated
(see Pre. 7).

Principle II

The application of names of taxonomic groups is determined by means of
nomenclatural types.

Principle III

The nomenclature of a taxonomic group is based upon priority of publica-
tion.

Principle IV

Each taxonomic group with a particular circumscription, position, and
rank can bear only one correct name, the earliest that is in accordance with
the Rules, except in specified cases.

Principle V

Scientific names of taxonomic groups are treated as Latin regardless of
their derivation.

Principle VI

The Rules of nomenclature are retroactive unless expressly limited.

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DIVISION II. RULES AND RECOMMENDATIONS
 
 

CHAPTER I. TAXA AND THEIR RANKS
 
 

Article 1

1.1.  Taxonomic groups of any rank will, in this Code, be referred to as
taxa (singular: taxon).

1.2.  Fossil taxa may be treated as morphotaxa. A morphotaxon is defined
as a fossil taxon which, for nomenclatural purposes, comprises only the
parts, life-history stages, or preservational states represented by the corre-
sponding nomenclatural type.

1.3.  As in the case of form-taxa for asexual forms (anamorphs) of certain
pleomorphic fungi (Art. 59), the provisions of this Code authorize the
publication and use of names of morphotaxa (Art. 11.7).

Article 2

2.1.  Every individual plant is treated as belonging to an indefinite number
of taxa of consecutively subordinate rank, among which the rank of spec-
cies (species) is basic.

Article 3

3.1.  The principal ranks of taxa in descending sequence are: kingdom
(regnum), division or phylum (divisio, phylum), class (classis), order
(ordo), family (familia), genus (genus), and species (species). Thus, each
species is assignable to a genus, each genus to a family, etc.

3.2.  The principal ranks of nothotaxa (hybrid taxa) are nothogenus and
nothospecies. These ranks are the same as genus and species. The addition
of “notho” indicates the hybrid character (see App. I).

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Article 4

4.1.  The secondary ranks of taxa in descending sequence are tribe (tribus)
between family and genus, section (sectio) and series (series) between
genus and species, and variety (varietas) and form (forma) below species.

4.2.  If a greater number of ranks of taxa is desired, the terms for these
are made by adding the prefix “sub-” to the terms denoting the principal or
secondary ranks. A plant may thus be assigned to taxa of the following
ranks (in descending sequence): regnum, subregnum, divisio or phylum,
subdivisio or subphylum, classis, subclassis, ordo, subordo, familia, sub-
familia, tribus, subtribus, genus, subgenus, sectio, subsectio, series, sub-
series, species, subspecies, varietas, subvarietas, forma, subforma.

4.3.  Further ranks may also be intercalated or added, provided that confu-
sion or error is not thereby introduced.

4.4.  The subordinate ranks of nothotaxa are the same as the subordinate
ranks of non-hybrid taxa, except that nothogenus is the highest rank per-
mitted (see App. I).

Note 1.  Throughout this Code the phrase “subdivision of a family” refers only to
taxa of a rank between family and genus and “subdivision of a genus” refers only
to taxa of a rank between genus and species.

Note 2.  For the designation of certain categories of plants used in agriculture,
forestry, and horticulture, see Art. 28 Notes 2-5.

Note 3.  In classifying parasites, especially fungi, authors who do not give spe-
cific, subspecific, or varietal value to taxa characterized from a physiological
standpoint but scarcely or not at all from a morphological standpoint may distin-
guish within the species special forms (formae speciales) characterized by their
adaptation to different hosts, but the nomenclature of special forms is not gov-
erned by the provisions of this Code.

Article 5

5.1.  The relative order of the ranks specified in Art. 3 and 4 must not be
altered (see Art. 33.7 and 33.8).

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CHAPTER II. STATUS, TYPIFICATION, AND PRIORITY OF

NAMES

SECTION 1. STATUS DEFINITIONS

Article 6

6.1.  Effective publication is publication in accordance with Art. 29-31.

6.2.  Valid publication of names is publication in accordance with Art. 32-
45 or H.9 (see also Art. 61).

6.3.  In this Code, unless otherwise indicated, the word “name” means a
name that has been validly published, whether it is legitimate or illegiti-
mate (see Art. 12).

Note 1.  When the same name, based on the same type, has been published inde-
pendently at different times by different authors, then only the earliest of these so-
called “isonyms” has nomenclatural status. The name is always to be cited from
its original place of valid publication, and later “isonyms” may be disregarded.

Ex. 1.  Baker (Summary New Ferns: 9. 1892) and Christensen (Index Filic: 44. 1905)
independently published the name Alsophila kalbreyeri as a substitute for A. podophylla
Baker (1891) non Hook. (1857). As published by Christensen, Alsophila kalbreyeri is a
later “isonym” of A. kalbreyeri Baker, without nomenclatural status (see also Art. 33 Ex.
10).

Ex. 2.  In publishing “Canarium pimela Leenh. nom. nov.”, Leenhouts (in Blumea 9: 406.
1959) reused the illegitimate C. pimela K. D. König (1805), attributing it to himself and
basing it on the same type. He thereby created a later “isonym” without nomenclatural
status.

6.4.  An illegitimate name is one that is designated as such in Art. 18.3,
19.5, or 52-54 (see also Art. 21 Note 1 and Art. 24 Note 2). A name which
according to this Code was illegitimate when published cannot become
legitimate later unless it is conserved or sanctioned.

Ex. 3.  Anisothecium Mitten (1869) when published included the previously designated
type of Dicranella (Müll. Hal.) Schimp. (1856). When Dicranella was conserved with a
different type, Anisothecium did not thereby become legitimate.

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Ex. 4.  Skeletonemopsis P. A. Sims (1995) was illegitimate when published because it
included the original type of Skeletonema Grev. (1865). When Skeletonema was conserved
with a different type, Skeletonemopsis nevertheless remained illegitimate and had to be
conserved in order to be available for use.

6.5.  A legitimate name is one that is in accordance with the rules, i.e., that
is not illegitimate as defined in Art. 6.4.

6.6.  At the rank of family or below, the correct name of a taxon with a
particular circumscription, position, and rank is the legitimate name which
must be adopted for it under the rules (see Art. 11).

Ex. 5.  The generic name Vexillifera Ducke (1922), based on the single species V. micran-
thera, is legitimate. The same is true of the generic name Dussia Krug & Urb. ex Taub.
(1892), based on the single species D. martinicensis. Both generic names are correct when
the genera are thought to be separate. Harms (in Repert. Spec. Nov. Regni Veg. 19: 291.
1924), however, united Vexillifera and Dussia in a single genus; the latter name is the
correct one for the genus with this particular circumscription. The legitimate name Vexil-
lifera may therefore be correct or incorrect according to different taxonomic concepts.

6.7.  The name of a taxon below the rank of genus, consisting of the name
of a genus combined with one or two epithets, is termed a combination
(see Art. 21, 23, and 24).

Ex. 6.  Combinations: Mouriri subg. Pericrene, Arytera sect. Mischarytera, Gentiana
lutea, Gentiana tenella var. occidentalis, Equisetum palustre var. americanum, Equisetum
palustre f. fluitans.

6.8.  Autonyms are such names as can be established automatically under
Art. 22.3 and 26.3, whether or not they appear in print in the publication
in which they are created (see Art. 32.6).

SECTION 2. TYPIFICATION

Article 7

7.1.  The application of names of taxa of the rank of family or below is
determined by means of nomenclatural types (types of names of taxa).
The application of names of taxa in the higher ranks is also determined by
means of types when the names are ultimately based on generic names
(see Art. 10.7).

7.2.  A nomenclatural type (typus) is that element to which the name of a
taxon is permanently attached, whether as a correct name or as a syn-

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onym. The nomenclatural type is not necessarily the most typical or repre-
sentative element of a taxon.

7.3.  A new name published as an avowed substitute (replacement name,
nomen novum) for an older name is typified by the type of the older name
(see Art. 33.3; but see Art. 33 Note 2).

Ex. 1.  Myrcia lucida McVaugh (1969) was published as a nomen novum for M. laevis
O. Berg (1862), an illegitimate homonym of M. laevis G. Don (1832). The type of M. luci-
da is therefore the type of M. laevis O. Berg (non G. Don), namely, Spruce 3502.

7.4.  A new name formed from a previously published legitimate name
(stat. nov., comb. nov.) is, in all circumstances, typified by the type of the
basionym, even though it may have been applied erroneously to a taxon
now considered not to include that type (but see Art. 48.1 and 59.6).

Ex. 2.  Pinus mertensiana Bong. was transferred to the genus Tsuga by Carrière, who,
however, as is evident from his description, erroneously applied the new combination T.
mertensiana to another species of Tsuga, namely T. heterophylla (Raf.) Sarg. The combi-
nation Tsuga mertensiana (Bong.) Carrière must not be applied to T. heterophylla but must
be retained for P. mertensiana when that species is placed in Tsuga; the citation in paren-
theses (under Art. 49) of the name of the original author, Bongard, indicates the type of the
name.

Ex. 3.  Delesseria gmelinii J. V. Lamour. (1813), an illegitimate replacement name for
Fucus palmetta S. G. Gmel. (1768), and all intended combinations based on D. gmelinii
(and not excluding the type of F. palmetta; see Art. 48.1) have the same type as F. pal-
metta, even though the material in Lamouroux’s hands is now assigned to a different spe-
cies, Delesseria bonnemaisonii C. Agardh (1822).

7.5.  A name which, under Art. 52, was illegitimate when published is
either automatically typified by the type of the name which ought to have
been adopted under the rules, or by a different type designated or defi-
nitely indicated by the author of the illegitimate name. Automatic typifi-
cation does not apply to names sanctioned under Art. 15.

7.6.  The type of an autonym is the same as that of the name from which it
is derived.

7.7.  A name validly published by reference to a previously and effec-
tively published description or diagnosis (Art. 32.1(c)) is to be typified by
an element selected from the context of the validating description or diag-
nosis, unless the validating author has definitely designated a different
type (but see Art. 10.2). However, the type of a name of a taxon assigned
to a group with a nomenclatural starting-point later than 1753 (see Art.
13.1) is to be determined in accordance with the indication or descriptive
and other matter accompanying its valid publication (see Art. 32-45).

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Ex. 4.  Since the name Adenanthera bicolor Moon (1824) is validated solely by reference
to Rumphius (Herb. Amboin. 3: t. 112. 1743), the type of the name, in the absence of the
specimen from which it was figured, is the illustration referred to. It is not the specimen, at
Kew, collected by Moon and labelled “Adenanthera bicolor”, since Moon did not defi-
nitely designate the latter as the type.

Ex. 5.  Echium lycopsis L. (Fl. Angl.: 12. 1754) was published without a description or
diagnosis but with reference to Ray (Syn. Meth. Stirp. Brit., ed. 3: 227. 1724), in which a
“Lycopsis” species was discussed with no description or diagnosis but with citation of
earlier references, including Bauhin (Pinax: 255. 1623). The accepted validating descrip-
tion of E. lycopsis is that of Bauhin, and the type must be chosen from the context of his
work. Consequently the Sherard specimen in the Morison herbarium (OXF), selected by
Klotz (in Wiss. Z. Martin-Luther-Univ. Halle-Wittenberg Math.-Naturwiss. Reihe 9: 375-
376. 1960), although probably consulted by Ray, is not eligible as type. The first accept-
able choice is that of the illustration, cited by both Ray and Bauhin, of “Echii altera spe-
cies” in Dodonaeus (Stirp. Hist. Pempt.: 620. 1583), suggested by Gibbs (in Lagascalia 1:
60-61. 1971) and formally made by Stearn (in Ray Soc. Publ. 148, Introd.: 65. 1973).

7.8.  Typification of names adopted in one of the works specified in Art.
13.1(d), and thereby sanctioned (Art. 15), may be effected in the light of
anything associated with the name in that work.

7.9.  The typification of names of morphogenera of plant fossils (Art. 1.2),
of fungal anamorphs (Art. 59), and of any other analogous genera or lower
taxa does not differ from that indicated above.

Note 1.  See also Art. 59 for details regarding typification of names in certain
pleomorphic fungi.

7.10.  For purposes of priority (Art. 9.17 and 10.5), designation of a type
is achieved only by effective publication (Art. 29-31).

7.11.  For purposes of priority (Art. 9.17 and 10.5), designation of a type
is achieved only if the type is definitely accepted as such by the typifying
author, if the type element is clearly indicated by direct citation including
the term “type” (typus) or an equivalent, and, on or after 1 January 2001,
if the typification statement includes the phrase “here designated” (hic
designatus) or an equivalent.

Ex. 6.  Chlorosarcina Gerneck (1907) originally comprised two species, C. minor and C.
elegans. Vischer (1933) transferred the former to Chlorosphaera G. A. Klebs and retained
the latter in Chlorosarcina. He did not, however, use the term “type” or an equivalent, so
that his action does not constitute typification of Chlorosarcina. The first to designate a
type, as “LT.”, was Starr (in ING Card No. 16528, Nov 1962), who selected Chlorosar-
cina elegans.

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*Ex. 7.  The phrase “standard species” as used by Hitchcock & Green (in Anon., Nomencl.
Prop. Brit. Botanists: 110-199. 1929) is now treated as equivalent to “type”, and hence
type designations in this work are acceptable.

Recommendation 7A

7A.1.  It is strongly recommended that the material on which the name of a taxon
is based, especially the holotype, be deposited in a public herbarium or other
public collection with a policy of giving bona fide botanists open access to de-
posited material, and that it be scrupulously conserved.

Article 8

8.1.  The type (holotype, lectotype, or neotype) of a name of a species or
infraspecific taxon is either a single specimen conserved in one herbarium
or other collection or institution, or an illustration.

8.2.  For the purpose of typification a specimen is a gathering, or part of a
gathering, of a single species or infraspecific taxon made at one time, dis-

regarding admixtures (see Art. 9.12). It may consist of a single plant, parts
of one or several plants, or of multiple small plants. A specimen is usually
mounted on a single herbarium sheet or in an equivalent preparation, such
as a box, packet, jar or microscope slide.

Ex. 1.  “Echinocereus sanpedroensis” (Raudonat & Rischer in Echinocereenfreund
8(4): 91-92. 1995) was based on a “holotype” consisting of a complete plant with
roots, a detached branch, an entire flower, a flower cut in halves, and two fruits,
which according to the label were taken from the same cultivated individual at differ-
ent times and preserved, in alcohol, in a single jar. This material belongs to more than
one gathering and cannot be accepted as a type. Raudonat & Rischer’s name is not
validly published under Art. 37.2.

8.3.  A specimen may be mounted as more than one preparation, as long
as the parts are clearly labelled as being part of that same specimen. Mul-
tiple preparations from a single gathering which are not clearly labelled as
being part of a single specimen are duplicates ¹, irrespective of whether
the source was one plant or more than one (but see Art. 8.5).

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* Here and elsewhere in the Code, a prefixed asterisk denotes a “voted Example”, accepted
   by a Congress in order to legislate nomenclatural practice when the corresponding Article
   of the Code is open to divergent interpretration or does not adequately cover the matter.

¹  Here and elsewhere in this Code, the word duplicate is given its usual meaning in her-
   barium curatorial practice. It is part of a single gathering of a single species or in-
   fraspecific taxon made by the same collector(s) at one time. The possibility of a mixed
   gathering must always be considered by an author choosing a lectotype, and corre-
   sponding caution used.

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Ex. 2.  The holotype specimen of Delissea eleeleensis H. St. John, Christensen 261
(BISH), is mounted as two preparations, a herbarium sheet (BISH No. 519675) bear-
ing the annotation “fl. bottled” and an inflorescence preserved in alcohol in a jar la-
belled “Cyanea, Christensen 261”. The annotation indicates that the inflorescence is
part of the holotype specimen and not a duplicate, nor is it part of the isotype speci-
men (BISH No. 519676), which is not labelled as including additional material pre-
served in a separate preparation.

Ex. 3.  The holotype specimen of Johannesteijsmannia magnifica J. Dransf., Drans-
field 862 (K), consists of a leaf mounted on five herbarium sheets, an inflorescence
and infructescence in a box, and liquid-preserved material in a bottle.

Ex. 4.  The holotype of Cephaëlis acanthacea Steyerm., Cuatrecasas 16752 (F), con-
sists of a single specimen mounted on two herbarium sheets, labelled “sheet 1” and
“sheet 2”. Although the two sheets have separate herbarium numbers, F-1153741 and
F-1153742, respectively, the cross-labelling indicates that they constitute a single
specimen. A third sheet of Cuatrecasas 16572, F-1153740, is not cross-labelled and is
therefore a duplicate.

Ex. 5.  The holotype specimen of Eugenia ceibensis Standl., Yuncker & al. 8309, is
mounted on a single herbarium sheet at F. A fragment was removed from the speci-
men subsequent to its designation as holotype and is now conserved in LL. The frag-
ment is mounted on a herbarium sheet along with a photograph of the holotype and is
labelled “fragment of type!”. The fragment is no longer part of the holotype specimen
because it is not permanently conserved in the same herbarium as the holotype. Such
fragments have the status of a duplicate, i.e. an isotype.

8.4.  Type specimens of names of taxa must be preserved permanently and
may not be living plants or cultures. However, cultures of fungi and algae,
if preserved in a metabolically inactive state (e.g. by lyophilization or
deep-freezing), are acceptable as types.

Ex. 6.  The strain CBS 7351 is acceptable as the type of the name Candida populi Hagler
& al. (in Int. J. Syst. Bacteriol. 39: 98. 1989) because it is permanently preserved in a
metabolically inactive state by lyophilization (see also Rec. 8B.2).

8.5.  The type, epitypes (Art. 9.7) excepted, of the name of a taxon of
fossil plants of the rank of species or below is always a specimen (see Art.
9.13). One whole specimen is to be considered as the nomenclatural type
(see Rec. 8A.3).

Recommendation 8A

8A.1.  When a holotype, a lectotype, or a neotype is an illustration, the specimen
or specimens upon which that illustration is based should be used to help deter-
mine the application of the name (see also Art. 9.13).

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8A.2.  When an illustration is designated as the type of a name under Art. 37.4,
the collection data of the illustrated material should be given (see also Rec.
32D.2).

8A.3.  If the type specimen of a name of a fossil plant is cut into pieces (sections
of fossil wood, pieces of coalball plants, etc.), all parts originally used in estab-
lishing the diagnosis ought to be clearly marked.

8A.4.  When a single specimen designated as type is mounted as multiple prepa-
rations, this should be stated in the protologue ¹, and the preparations appropri-
ately labelled.

Recommendation 8B

8B.1.  Whenever practicable a living culture should be prepared from the holo-
type material of the name of a newly described taxon of fungi or algae and de-
posited in at least two institutional culture or genetic resource collections. (Such
action does not obviate the requirement for a holotype specimen under Art. 8.4.)

8B.2.  In cases where the type of a name is a culture permanently preserved in a
metabolically inactive state (see Art. 8 Ex. 6), any living isolates obtained from
that should be referred to as “ex-type” (ex typo), “ex-holotype” (ex holotypo),
“ex-isotype” (ex isotypo), etc., in order to make it clear they are derived from the
type but are not themselves the nomenclatural type.

Article 9

9.1.  A holotype of a name of a species or infraspecific taxon is the one
specimen or illustration (but see Art. 37.4) used by the author, or desig-
nated by the author as the nomenclatural type. As long as a holotype is
extant, it fixes the application of the name concerned (but see Art. 9.13;
see also Art. 10).

Note 1.  Any designation made by the original author, if definitely expressed at
the time of the original publication of the name of the taxon, is final (but see Art.
9.9 and 9.13). If the author used only one element, that one must be accepted as
the holotype. If a new name is based on a previously published description or
diagnosis of the taxon, the same considerations apply to material included by the
earlier author (see Art. 7.7 and 7.8).

9.2.  A lectotype is a specimen or illustration designated from the original
material as the nomenclatural type, in conformity with Art. 9.9 and 9.10,

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¹ Protologue (from the Greek protos, first; logos, discourse): everything associated with a
  name at its valid publication, i.e. description or diagnosis, illustrations, references, syn-
  onymy, geographical data, citation of specimens, discussion, and comments.

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if no holotype was indicated at the time of publication, or if it is missing,
or if it is found to belong to more than one taxon (see also Art. 9.13).

Note 2.  For the purposes of this Code, the original material comprises: (a) those
specimens and illustrations (both unpublished and published either prior to or
together with the protologue) upon which it can be shown that the description or
diagnosis validating the name was based; (b) the holotype and those specimens
which, even if not seen by the author of the description or diagnosis validating the
name, were indicated as types (syntypes or paratypes) of the name at its valid
publication; and (c) the isotypes or isosyntypes of the name irrespective of
whether such specimens were seen by either the author of the validating descrip-
tion or diagnosis, or the author of the name.

9.3.  An isotype is any duplicate of the holotype; it is always a specimen.

9.4.  A syntype is any specimen cited in the protologue when no holotype
was designated, or any one of two or more specimens simultaneously des-
ignated as types.

9.5.  A paratype is a specimen cited in the protologue that is neither the
holotype nor an isotype, nor one of the syntypes if two or more specimens
were simultaneously designated as types.

Ex. 1.   The holotype of the name Rheedia kappleri Eyma, which applies to a polygamous
species, is a male specimen collected by Kappler (593a in U). The author designated a
hermaphroditic specimen collected by the Forestry Service of Surinam as a paratype
(B. W. 1618 in U).

Note 3.  In most cases in which no holotype was designated there will also be no
paratypes, since all the cited specimens will be syntypes. However, when an
author designated two or more specimens as types (Art. 9.4), any remaining cited
specimens are paratypes and not syntypes.

9.6.  A neotype is a specimen or illustration selected to serve as nomen-
clatural type as long as all of the material on which the name of the taxon
was based is missing (see also Art. 9.15).

9.7.  An epitype is a specimen or illustration selected to serve as an inter-
pretative type when the holotype, lectotype, or previously designated
neotype, or all original material associated with a validly published name,
is demonstrably ambiguous and cannot be critically identified for pur-
poses of the precise application of the name of a taxon. When an epitype
is designated, the holotype, lectotype, or neotype that the epitype supports
must be explicitly cited (see Art. 9.18).

Ex. 2.   The holotype of Vitellaria paradoxa C. F. Gaertn. (1807) is a seed of unknown
provenance (P), clearly belonging to the species currently known as Butyrospermum para-
doxum (C. F. Gaertn.) Hepper. However, the two subspecies recognized within that species

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can only be distinguished by characters of foliage or inflorescence. Hall & Hurdle (in
Taxon 44: 410. 1995) designated an epitype with foliage, Mungo Park (BM). It belongs to
the western subspecies, now to be known as B. paradoxum subsp. paradoxum.

9.8.  The use of a term defined in the Code (Art. 9.1-9.7) as denoting
a type, in a sense other than that in which it is so defined, is treated as an
error to be corrected (for example, the use of the term lectotype to denote
what is in fact a neotype).

Ex. 3.   Borssum Waalkes (in Blumea 14: 198. 1966) cited Herb. Linnaeus No. 866.7
(LINN) as the holotype of Sida retusa L. (1763). The term is incorrectly used because
illustrations in Plukenet (Phytographia: t. 9, f. 2. 1691) and Rumphius (Herb. Amboin. 6:
t. 19. 1750) were cited by Linnaeus in the protologue of S. retusa. Since all three elements
are original material (Art. 9 Note 2), Borssum Waalkes’s use of holotype is an error to be
corrected to lectotype.

Ex. 4.   In describing the Jurassic dinoflagellate species Nannoceratopsis triceras, Drugg
(1978) designated a holotype (slide preparation) and one isotype (SEM preparation) from
the same locality, age, and zone. He also cited two other specimens which are from a
different locality, stage, and zone as “isotypes”. Drugg’s second use of the term isotype is
an error and is to be corrected to “paratype”.

9.9.  If no holotype was indicated by the author of a name of a species or
infraspecific taxon, or when the holotype has been lost or destroyed, or
when the material designated as type is found to belong to more than one
taxon, a lectotype or, if permissible (Art. 9.6), a neotype as a substitute for
it may be designated (Art. 7.10 and 7.11).

9.10.  In lectotype designation, an isotype must be chosen if such exists,
or otherwise a syntype if such exists. If no isotype, syntype or isosyntype
(duplicate of syntype) is extant, the lectotype must be chosen from among
the paratypes if such exist. If no cited specimens exist, the lectotype must
be chosen from among the uncited specimens and cited and uncited illus-
trations which comprise the remaining original material, if such exist.

9.11.  If no original material is extant, a neotype may be selected. A lec-
totype always takes precedence over a neotype, except as provided by Art.
9.15.  

9.12.  When a type specimen (herbarium sheet or equivalent preparation)
contains parts belonging to more than one taxon (see Art. 9.9), the name
must remain attached to that part which corresponds most nearly with the
original description or diagnosis.

Ex. 5.   The type of the name Tillandsia bryoides Griseb. ex Baker (1878) is Lorentz 128
(BM); this specimen, however, proved to be mixed. Smith (in Proc. Amer. Acad. Arts 70:
192. 1935) acted in accordance with Art. 9.12 in designating one part of Lorentz’s speci-
men as the lectotype.

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9.13.  The holotype (or lectotype) of a name of a species or infraspecific
taxon of fossil plants (Art. 8.5) is the specimen (or one of the specimens)
on which the validating illustrations (Art. 38) are based. When, prior to
1 January 2001 (see Art. 38.2), in the protologue of a name of a new taxon
of fossil plants of the rank of species or below, a type specimen is indi-
cated (Art. 37.1) but not identified among the validating illustrations, a
lectotype must be designated from among the specimens illustrated in the
protologue. This choice is superseded if it can be demonstrated that the
original type specimen corresponds to another validating illustration.

9.14.  A designation of a lectotype or neotype that later is found to refer to
a single gathering but more than one specimen must nevertheless be ac-
cepted (subject to Art. 9.17), but may be further narrowed to a single one
of these specimens by way of a subsequent lectotypification or neotypifi-
cation.

Ex. 6.   Erigeron plantagineus Greene (1898) was described from material collected by R.
M. Austin in California. Cronquist (in Brittonia 6: 173. 1947) wrote “Type: Austin s.n.,
Modoc County, California (ND)”, thereby designating the Austin material in ND as the
[first-step] lectotype. Strother & Ferlatte (in Madroño 35: 85. 1988), noting that there were
two specimens of this gathering at ND, designated one of them (ND-G No. 057228) as the
[second-step] lectotype. In subsequent references, both lectotypification steps may be cited
in sequence.

9.15.  When a holotype or a previously designated lectotype has been lost
or destroyed and it can be shown that all the other original material differs
taxonomically from the destroyed type, a neotype may be selected to pre-
serve the usage established by the previous typification (see also Art.
9.16).

9.16.  A neotype selected under Art. 9.15 may be superseded if it can be
shown to differ taxonomically from the holotype or lectotype that it re-
placed.

9.17.  The author who first designates a lectotype or a neotype must be
followed, but that choice is superseded if (a) the holotype or, in the case
of a neotype, any of the original material is rediscovered; the choice may
also be superseded if one can show that (b) it is in serious conflict with the
protologue and another element is available that is not in conflict with the
protologue, or that (c) it is contrary to Art. 9.12.

9.18.  The author who first designates an epitype must be followed; a dif-
ferent epitype may be designated only if the original epitype is lost or de-
stroyed. A lectotype or neotype supported by an epitype may be superseded
in accordance with Art. 9.17 or, in the case of a neotype, Art. 9.16. If it
can be shown that an epitype and the type it supports differ taxonomically

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and that neither Art. 9.16 nor 9.17 applies, the name may be proposed for
conservation with a conserved type (Art. 14.9; see also Art. 57).

Note 4.  An epitype supports only the type to which it is linked by the typifying
author. If the supported type is superseded, the epitype has no standing with re-
spect to the replacement type.

9.19.  Designation of an epitype is not effected unless the herbarium or
institution in which the epitype is conserved is specified or, if the epitype
is a published illustration, a full and direct bibliographic reference to it is
provided.

9.20.  On or after 1 January 1990, lectotypification or neotypification of a
name of a species or infraspecific taxon by a specimen or unpublished
illustration is not effected unless the herbarium or institution in which the
type is conserved is specified.

9.21.  On or after 1 January 2001, lectotypification or neotypification of a
name of a species or infraspecific taxon is not effected unless indicated
by use of the term “lectotypus” or “neotypus”, its abbreviation, or its
equivalent in a modern language (but see Art. 9.8).

Recommendation 9A

9A.1.  Typification of names for which no holotype was designated should only
be carried out with an understanding of the author’s method of working; in par-
ticular it should be realized that some of the material used by the author in de-
scribing the taxon may not be in the author’s own herbarium or may not even
have survived, and conversely, that not all the material surviving in the author’s
herbarium was necessarily used in describing the taxon.

9A.2.  Designation of a lectotype should be undertaken only in the light of an
understanding of the group concerned. In choosing a lectotype, all aspects of the
protologue should be considered as a basic guide. Mechanical methods, such as
the automatic selection of the first element cited or of a specimen collected by the
person after whom a species is named, should be avoided as unscientific and
productive of possible future confusion and further changes.

9A.3.  In choosing a lectotype, any indication of intent by the author of a name
should be given preference unless such indication is contrary to the protologue.
Such indications are manuscript notes, annotations on herbarium sheets, recog-
nizable figures, and epithets such as typicus, genuinus, etc.

9A.4.  When a single collection is cited in the protologue, but a particular institu-
tion housing this is not designated, it should be assumed that the specimen housed
in the institution where the author is known to have worked is the holotype, un-
less there is evidence that further material of the same collection was used.

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9A.5.  When two or more heterogeneous elements were included in or cited with
the original description or diagnosis, the lectotype should be so selected as to
preserve current usage. In particular, if another author has already segregated one
or more elements as other taxa, the residue or part of it should be designated as
the lectotype provided that this element is not in conflict with the original de-
scription or diagnosis (see Art. 9.17).

Recommendation 9B

9B.1.  In selecting a neotype, particular care and critical knowledge should be
exercised because the reviewer usually has no guide except personal judgement
as to what best fits the protologue; if this selection proves to be faulty it will in-
evitably result in further change.

Article 10

10.1.  The type of a name of a genus or of any subdivision of a genus is
the type of a name of a species (except as provided by Art. 10.4). For pur-
poses of designation or citation of a type, the species name alone suffices,
i.e., it is considered as the full equivalent of its type.

Note 1.  Terms such as “holotype”, “syntype”, and “lectotype”, as presently de-
fined in Art. 9, although not applicable, strictly speaking, to the types of names in
ranks higher than species, are so used by analogy.

10.2.  If in the protologue of the name of a genus or of any subdivision of
a genus the holotype or lectotype of one or more previously or simultane-
ously published species name(s) is definitely included (see Art. 10.3), the
type must be chosen (Art. 7.10 and 7.11) from among these types unless
the type was indicated (Art. 22.6, 22.7, 37.1 and 37.3) or designated by
the author of the name. If no type of a previously or simultaneously pub-
lished species name was definitely included, a type must be otherwise
chosen, but the choice is to be superseded if it can be demonstrated that
the selected type is not conspecific with any of the material associated
with the protologue.

Ex. 1.  The genus Anacyclus, as originally circumscribed by Linnaeus (1753), comprised
three validly named species. Cassini (in Cuvier, Dict. Sci. Nat. 34: 104. 1825) designated
Anthemis valentina L. (1753) as type of Anacyclus, but this was not an original element of
the genus. Green (in Anon., Nomencl. Prop. Brit. Botanists: 182. 1929) designated Anacy-
clus valentinus L. (1753), “the only one of the three original species still retained in the
genus”, as the “standard species” (see Art. 7 Ex. 7), and her choice must be followed (Art.
10.5). Humphries (in Bull. Brit. Mus. (Nat. Hist.) Bot. 7: 109. 1979) designated a specimen
in the Clifford Herbarium (BM) as lectotype of Anacyclus valentinus, and that specimen
thereby became the ultimate type of the generic name.

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Ex. 2.  Castanella Spruce ex Benth. & Hook. f. (1862) was described on the basis of a
single specimen and without mention of a species name. Swart (in ING Card No. 2143.
1957) was the first to designate a type (as “T.”): C. granatensis Triana & Planch. (1862),
based on a Linden collection. As long as the Spruce specimen is considered to be con-
specific with Linden’s collection Swart’s type designation cannot be superseded, even
though the Spruce specimen became the type of Paullinia paullinioides Radlk. (1896), be-
cause the latter is not a “previously or simultaneously published species name”.

10.3.  For the purposes of Art. 10.2, definite inclusion of the type of a
name of a species is effected by citation of, or reference (direct or indi-
rect) to, a validly published name, whether accepted or synonymized by
the author, or by citation of the holotype or lectotype of a previously or
simultaneously published name of a species.

Ex. 3.  The protologue of Elodes Adans. (1763) included references to “Elodes” of Clusius
(1601), “Hypericum” of Tournefort (1700), and Hypericum aegypticum L. (1753). The
latter is the only reference to a validly published name of a species, and neither of the other
elements is the type of a name of a species. The type of H. aegypticum is therefore the type
of Elodes, even though subsequent authors designated H. elodes L. (1759) as the type (see
Robson in Bull. Brit. Mus. (Nat. Hist.), Bot. 5: 305, 336. 1977).

10.4.  By and only by conservation (Art. 14.9), the type of a name of a
genus may be a specimen or illustration, preferably used by the author in
the preparation of the protologue, other than the type of a name of an in-
cluded species.

Ex. 4.  Physconia Poelt (1965) was originally conserved with the specimen “‘Lichen pul-
verulentus’, Germania, Lipsia in Tilia, 1767, Schreber (M)” as the type. That specimen is
the type of P. pulverulacea Moberg (1979), which name is now cited in the type entry in
App. IIIA.

Note 2.  If the element designated under Art. 10.4 is the type of a species name,
that name may be cited as the type of the generic name. If the element is not the
type of a species name, a parenthetical reference to the correct name of the type
element may be added.

Ex. 5.  Pseudolarix Gordon (1858) was conserved with a specimen from the Gordon her-
barium as its conserved type. As this specimen is not the type of any species name, its
accepted identity “[= P. amabilis (J. Nelson) Rehder ... ]” has been added to the corre-
sponding entry in App. IIIA.

10.5.  The author who first designates a type of a name of a genus or sub-
division of a genus must be followed, but the choice may be superseded if
(a) it can be shown that it is in serious conflict with the protologue and an-
other element is available which is not in conflict with the protologue, or
(b) that it was based on a largely mechanical method of selection.

Ex. 6.  Fink (in Contr. U.S. Natl. Herb. 14(1): 2. 1910) specified that he was “stating the
types of the genera according to the ‘first species’ rule”. His type designations may there-
fore be superseded. For example, Fink had designated Biatorina griffithii (Ach.) A. Mas-

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sal. as the type of Biatorina A. Massal.; but his choice was superseded when the next
subsequent designation, by Santesson (in Symb. Bot. Upsal. 12(1): 428. 1952), stated a
different type, B. atropurpurea (Schaerer) A. Massal.

*Ex. 7.  Authors following the American code of botanical nomenclature, Canon 15 (in
Bull. Torrey Bot. Club 34: 172. 1907), designated as the type “the first binomial species in
order” eligible under certain provisions. This method of selection is to be considered as
largely mechanical. Thus the first type designation for Delphinium L., by Britton (in Brit-
ton & Brown, Ill. Fl. N. U.S., ed. 2, 2: 93. 1913), who followed the American code and
chose D. consolida L., has been superseded under Art. 10.5(b) by the designation of
D. peregrinum L. by Green (in Anon., Nomencl. Prop. Brit. Botanists: 162. 1929). The
unicarpellate D. consolida could not have been superseded as type by the tricarpellate
D. peregrinum under Art. 10.5(a), however, because it is not in serious conflict with the
generic protologue, which specifies “germina tria vel unum”, the assignment of the genus
to “Polyandria Trigynia” by Linnaeus notwithstanding.

10.6.  The type of a name of a family or of any subdivision of a family is
the same as that of the generic name on which it is based (see Art. 18.1).
For purposes of designation or citation of a type, the generic name alone
suffices. The type of a name of a family or subfamily not based on a ge-
neric name is the same as that of the corresponding alternative name (Art.
18.5 and 19.7).

10.7.  The principle of typification does not apply to names of taxa above
the rank of family, except for names that are automatically typified by
being based on generic names (see Art. 16). The type of such a name is
the same as that of the generic name on which it is based.

Note 3.  For the typification of some names of subdivisions of genera see Art.
22.6 and 22.7.

Recommendation 10A

10A.1.  When a combination in a rank of subdivision of a genus has been pub-
lished under a generic name that has not yet been typified, the type of the generic
name should be selected from the subdivision of the genus that was designated as
nomenclaturally typical, if that is apparent.

SECTION 3. PRIORITY

Article 11

11.1.  Each family or taxon of lower rank with a particular circumscrip-
tion, position, and rank can bear only one correct name, special exceptions
being made for 9 families and 1 subfamily for which alternative names are
permitted (see Art. 18.5 and 19.7). However, the use of separate names for

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the form-taxa of fungi and for morphotaxa of fossil plants is allowed un-
der Art. 1.3 and 59.4-59.5.

11.2.  In no case does a name have priority outside the rank in which it is
published (but see Art. 53.4).

Ex. 1.  Campanula sect. Campanopsis R. Br. (Prodr.: 561. 1810) when treated as a genus
is called Wahlenbergia Roth (1821), a name conserved against the taxonomic (heterotypic)
synonym Cervicina Delile (1813), and not Campanopsis (R. Br.) Kuntze (1891).

Ex. 2.  Magnolia virginiana var. foetida L. (1753) when raised to specific rank is called
M. grandiflora L. (1759), not M. foetida (L.) Sarg. (1889).

Ex. 3.  Lythrum intermedium Ledeb. (1822) when treated as a variety of L. salicaria L.
(1753) is called L. salicaria var. glabrum Ledeb. (Fl. Ross. 2: 127. 1843), not L. salicaria
var. intermedium (Ledeb.) Koehne (in Bot. Jahrb. Syst. 1: 327. 1881).

Ex. 4.  When the two varieties constituting Hemerocallis lilioasphodelus L. (1753), var. flava
L. and var. fulva L., are considered to be distinct species, the one not including the lectotype
of the species name is called H. fulva (L.) L. (1762), but the other one bears the name H.
lilioasphodelus L., which in the rank of species has priority over H. flava (L.) L. (1762).

11.3.  For any taxon from family to genus inclusive, the correct name is
the earliest legitimate one with the same rank, except in cases of limitation
of priority by conservation (see Art. 14) or where Art. 11.7, 15, 19.4, 56,
57, or 59 apply.

Ex. 5.  When Aesculus L. (1753), Pavia Mill. (1754), Macrothyrsus Spach (1834) and
Calothyrsus Spach (1834) are referred to a single genus, its name is Aesculus L.

11.4.  For any taxon below the rank of genus, the correct name is the com-
bination of the final epithet¹ of the earliest legitimate name of the taxon in
the same rank, with the correct name of the genus or species to which it is
assigned, except (a) in cases of limitation of priority under Art. 14, 15, 56,
or 57, or (b) if the resulting combination would be invalid under Art.
32.1(b) or illegitimate under Art. 53, or (c) if Art. 11.7, 22.1, 26.1, or 59
rule that a different combination is to be used.

Ex. 6.  Primula sect. Dionysiopsis Pax (in Jahresber. Schles. Ges. Vaterländ. Kultur 87: 20.
1909) when transferred to Dionysia Fenzl becomes D. sect. Dionysiopsis (Pax) Melch. (in
Mitt. Thüring. Bot. Vereins 50: 164-168. 1943); the substitute name D. sect. Ariadna
Wendelbo (in Bot. Not. 112: 496. 1959) is illegitimate.

Ex. 7.  Antirrhinum spurium L. (1753) when transferred to Linaria Mill. is called L. spuria
(L.) Mill. (1768).

Ex. 8.  When transferring Serratula chamaepeuce L. (1753) to Ptilostemon Cass., Cassini
illegitimately named the species P. muticus Cass. (1826). In that genus, the correct name is
P. chamaepeuce (L.) Less. (1832).

———————————————————————

¹ Here and elsewhere in this Code, the phrase “final epithet” refers to the last epithet in
  sequence in any particular combination, whether in the rank of a subdivision of a genus,
  or of a species, or of an infraspecific taxon.

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Ex. 9.  Spartium biflorum Desf. (1798) when transferred to Cytisus Desf. could not be
called C. biflorus because of the previously and validly published C. biflorus L’Hér.
(1791); the substitute name C. fontanesii Spach (1849) was therefore correctly proposed.

Ex. 10.  Spergula stricta Sw. (1799) when transferred to Arenaria L. is called A. uliginosa
Schleich. ex Schltdl. (1808) because of the existence of the name A. stricta Michx. (1803),
based on a different type; but on further transfer to the genus Minuartia L. the epithet
stricta is again available and the species is called M. stricta (Sw.) Hiern (1899).

Ex. 11.  Arum dracunculus L. (1753) when transferred to Dracunculus Mill. is named
D. vulgaris Schott (1832), as use of the Linnaean epithet would result in a tautonym.

Ex. 12.  Cucubalus behen L. (1753) when transferred to Behen Moench was legitimately
renamed B. vulgaris Moench (1794) to avoid the tautonym “B. behen”. In Silene L., the
epithet behen is unavailable because of the existence of S. behen L. (1753). Therefore, the
substitute name S. cucubalus Wibel (1799) was proposed. This, however, is illegitimate
since the specific epithet vulgaris was available. In Silene, the correct name of the species
is S. vulgaris (Moench) Garcke (1869).

Ex. 13.  Helianthemum italicum var. micranthum Gren. & Godr. (Fl. France 1: 171. 1847)
when transferred as a variety to H. penicillatum Thibaud ex Dunal retains its varietal epi-
thet and is named H. penicillatum var. micranthum (Gren. & Godr.) Grosser (in Engler,
Pflanzenr. 14: 115. 1903).

Note 1.  The valid publication of a name at a rank lower than genus precludes any
simultaneous homonymous combination (Art. 53), irrespective of the priority of
other names with the same final epithet that may require transfer to the same
genus or species.

Ex. 14.  Tausch included two species in his new genus Alkanna: A. tinctoria Tausch
(1824), a new species based on “Anchusa tinctoria” in the sense of Linnaeus (1762), and
A. plukenetii Tausch 1824, a nomen novum based on Lithospermum tinctorium L. (1753).
Both names are legitimate and take priority from (1824).

Ex. 15.  Raymond-Hamet transferred to the genus Sedum both Cotyledon sedoides DC.
(1808) and Sempervivum sedoides Decne. (1844). He combined the epithet of the later
name, Sempervivum sedoides, under Sedum as S. sedoides (Decne.) Hamet (1929), and
published a new name, S. candollei Hamet (1929), for the earlier name. Both names are
legitimate.

11.5.  When, for any taxon of the rank of family or below, a choice is
possible between legitimate names of equal priority in the corresponding
rank, or between available final epithets of names of equal priority in the
corresponding rank, the first such choice to be effectively published (Art.
29-31) establishes the priority of the chosen name, and of any legitimate
combination with the same type and final epithet at that rank, over the
other competing name(s) (but see Art. 11.6).

Note 2.  A choice as provided for in Art. 11.5 is effected by adopting one of the
competing names, or its final epithet in the required combination, and simultane-
ously rejecting or relegating to synonymy the other(s), or nomenclatural (homo-
typic) synonyms thereof.

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Ex. 16.  When Dentaria L. (1753) and Cardamine L. (1753) are united, the resulting genus
is called Cardamine because that name was chosen by Crantz (Cl. Crucif. Emend.: 126.
1769), who first united them.

Ex. 17.  When Entoloma (Fr. ex Rabenh.) P. Kumm. (1871), Leptonia (Fr. : Fr.) P. Kumm.
(1871), Eccilia (Fr. : Fr.) P. Kumm. (1871), Nolanea (Fr. : Fr.) P. Kumm. (1871), and
Claudopus Gillet (1876) are united, one of the generic names simultaneously published by
Kummer must be used for the combined genus. Donk, who did so (in Bull. Jard. Bot.
Buitenzorg, ser. 3, 18(1): 157. 1949), selected Entoloma, which is therefore treated as
having priority over the other names.

Ex. 18.  Brown (in Tuckey, Narr. Exped. Zaire: 484. 1818) was the first to unite Waltheria
americana L. (1753) and W. indica L. (1753). He adopted the name W. indica for the com-
bined species, and this name is accordingly treated as having priority over W. americana.

Ex. 19.  Baillon (in Adansonia 3: 162. 1863), when uniting for the first time Sclerocroton
integerrimus Hochst. (1845) and S. reticulatus Hochst. (1845), adopted the name Stillingia
integerrima (Hochst.) Baill. for the combined taxon. Consequently Sclerocroton integer-
rimus is treated as having priority over S. reticulatus irrespective of the genus (Sclerocro-
ton, Stillingia, Excoecaria, Sapium) to which the species is assigned.

Ex. 20.  Linnaeus (1753) simultaneously published the names Verbesina alba and V. pro-
strata. Later (1771), he published Eclipta erecta, an illegitimate name because V. alba was
cited in synonymy, and E. prostrata, based on V. prostrata. The first author to unite these
taxa was Roxburgh (Fl. Ind. 3: 438. 1832), who adopted the name E. prostrata (L.) L.
Therefore V. prostrata is treated as having priority over V. alba.

Ex. 21.  Donia speciosa and D. formosa, which were simultaneously published by Don
(1832), were illegitimately renamed Clianthus oxleyi and C. dampieri by Lindley (1835).
Brown (1849) united both in a single species, adopting the illegitimate name C. dampieri
and citing D. speciosa and C. oxleyi as synonyms; his choice is not of the kind provided
for by Art. 11.5. C. speciosus (D. Don) Asch. & Graebn. (1909), published with D. spe-
ciosa and C. dampieri listed as synonyms, is an illegitimate later homonym of C. speciosus
(Endl.) Steud. (1840); again, conditions for a choice under Art. 11.5 were not satisfied.
Ford & Vickery (1950) published the legitimate combination C. formosus (D. Don) Ford &
Vickery and cited D. formosa and D. speciosa as synonyms, but since the epithet of the
latter was unavailable in Clianthus a choice was not possible and again Art. 11.5 does not
apply. Thompson (1990) was the first to effect an acceptable choice when publishing the
combination Swainsona formosa (D. Don) Joy Thomps. and indicating that D. speciosa
was a synonym of it.

11.6.  An autonym is treated as having priority over the name or names of
the same date and rank that established it.

Note 3.  When the final epithet of an autonym is used in a new combination under
the requirements of Art. 11.6, the basionym of that combination is the name from
which the autonym is derived, or its basionym if it has one.

Ex. 22.  Heracleum sibiricum L. (1753) includes H. sibiricum subsp. lecokii (Godr. &
Gren.) Nyman (Consp. Fl. Europ.: 290. 1879) and H. sibiricum subsp. sibiricum automati-
cally established at the same time. When H. sibiricum is included in H. sphondylium L.
(1753) as a subspecies, the correct name for the taxon is H. sphondylium subsp. sibiricum

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(L.) Simonk. (Enum. Fl. Transsilv.: 266. 1887), not subsp. lecokii, whether or not subsp.
lecokii is treated as distinct.

Ex. 23.  The publication of Salix tristis var. microphylla Andersson (Salices Bor.-Amer.:
21. 1858) created the autonym S. tristis Aiton (1789) var. tristis, dating from 1858. If
S. tristis, including var. microphylla, is recognized as a variety of S. humilis Marshall
(1785), the correct name is S. humilis var. tristis (Aiton) Griggs (in Proc. Ohio Acad. Sci.
4: 301. 1905). However, if both varieties of S. tristis are recognized as varieties of S. hu-
milis, then the names S. humilis var. tristis and S. humilis var. microphylla (Andersson)
Fernald (in Rhodora 48: 46. 1946) are both used.

Ex. 24.  In the classification adopted by Rollins and Shaw, Lesquerella lasiocarpa (Hook.
ex A. Gray) S. Watson (1888) is composed of two subspecies, subsp. lasiocarpa (which
includes the type of the name of the species and is cited without an author) and subsp. ber-
landieri (A. Gray) Rollins & E. A. Shaw. The latter subspecies is composed of two varie-
ties. In that classification the correct name of the variety which includes the type of subsp.
berlandieri is L. lasiocarpa var. berlandieri (A. Gray) Payson (1922), not L. lasiocarpa
var. berlandieri (cited without an author) or L. lasiocarpa var. hispida (S. Watson) Rollins
& E. A. Shaw (1972), based on Synthlipsis berlandieri var. hispida S. Watson (1882),
since publication of the latter name established the autonym S. berlandieri A. Gray var.
berlandieri which, at varietal rank, is treated as having priority over var. hispida.

11.7.  For purposes of priority, names of fossil taxa (diatoms excepted)
compete only with names based on a fossil type representing the same
part, life-history stage, or preservational state (see Art. 1.2).

Ex. 25.  The generic name Sigillaria Brongn. (1822), established for bark fragments, may
in part represent the same biological taxon as the “cone-genus” Mazocarpon M. J. Benson
(1918), which represents permineralizations, or Sigillariostrobus (Schimp.) Geinitz (1873),
which represents compressions. Certain species of all three genera, Sigillaria, Mazocar-
pon, and Sigillariostrobus, have been assigned to the family Sigillariaceae. All these
generic names can be used concurrently in spite of the fact that they may, at least in part,
apply to the same organism.

Ex. 26.  The morphogeneric name Tuberculodinium D. Wall (1967) may be retained for a
genus of fossil cysts even though cysts of the same kind are known to be part of the life
cycle of an extant genus that bears an earlier name, Pyrophacus F. Stein (1883).

Note 4.  Names of plants (diatoms excepted) based on a non-fossil type are
treated as having priority over names of the same rank based on a fossil (or sub-
fossil) type.

Ex. 27.  If Platycarya Siebold & Zucc. (1843), a non-fossil genus, and Petrophiloides
Bowerb. (1840), a fossil genus, are united, the name Platycarya is accepted for the com-
bined genus, although it is antedated by Petrophiloides.

Ex. 28.  Boalch and Guy-Ohlson (in Taxon 41: 529-531. 1992) united the two prasinophyte
genera Pachysphaera Ostenf. (1899) and Tasmanites E. J. Newton (1875). Pachysphaera
is based on a non-fossil type and Tasmanites on a fossil type. Under the Code in effect in
1992, Tasmanites had priority and was therefore adopted. Under the current Code, in
which the exemption in Art. 11.7 applies only to diatoms and not to algae in general,
Pachysphaera is correct for the combined genus.

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Ex. 29.  The generic name Metasequoia Miki (1941) was based on the fossil type of M.
disticha (Heer) Miki. After discovery of the non-fossil species M. glyptostroboides Hu
& W. C. Cheng, conservation of Metasequoia Hu & W. C. Cheng (1948) as based on the
non-fossil type was approved. Otherwise, any new generic name based on M. glyptostro-
boides would have had to be treated as having priority over Metasequoia Miki.

11.8.  For purposes of priority, names in Latin form given to hybrids are
subject to the same rules as are those of non-hybrid taxa of equivalent
rank.

Ex. 30.  The name ×Solidaster H. R. Wehrh. (1932) antedates ×Asterago Everett (1937) for
the hybrids between Aster L. and Solidago L.

Ex. 31.  Anemone ×hybrida Paxton (1848) antedates A. ×elegans Decne. (1852), pro sp., as
the binomial for the hybrids derived from A. hupehensis (Lemoine & E. Lemoine) Le-
moine & E. Lemoine × A. vitifolia Buch.-Ham. ex DC.

Ex. 32.  Camus (in Bull. Mus. Natl. Hist. Nat. 33: 538. 1927) published the name
×Agroelymus A. Camus for a nothogenus, without a Latin description or diagnosis, men-
tioning only the names of the parents involved (Agropyron Gaertn. and Elymus L.). Since
this name was not validly published under the Code then in force, Rousseau (in Mém. Jard.
Bot. Montréal 29: 10-11. 1952) published a Latin diagnosis. However, the date of valid
publication of ×Agroelymus under this Code (Art. H.9) is 1927, not 1952, so it antedates
the name ×Elymopyrum Cugnac (in Bull. Soc. Hist. Nat. Ardennes 33: 14. 1938).

11.9.  The principle of priority is not mandatory for names of taxa above
the rank of family (but see Rec. 16B).

Article 12

12.1.  A name of a taxon has no status under this Code unless it is validly
published (see Art. 32-45).

SECTION 4. LIMITATION OF THE PRINCIPLE OF PRIORITY

Article 13

13.1.  Valid publication of names for plants of the different groups is
treated as beginning at the following dates (for each group a work is men-
tioned which is treated as having been published on the date given for that
group):

Non-fossil plants:

(a)   Spermatophyta and Pteridophyta, 1 May 1753 (Linnaeus, Spe-
       cies plantarum, ed. 1).

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(b)   Musci (the Sphagnaceae excepted), 1 January 1801 (Hedwig, Species
       muscorum).

(c)   Sphagnaceae and Hepaticae, 1 May 1753 (Linnaeus, Species plan-
       tarum, ed. 1).

(d)   Fungi (including slime moulds and lichen-forming fungi), 1 May
       1753 (Linnaeus, Species plantarum, ed. 1). Names in the Uredinales,
       Ustilaginales, and Gasteromycetes (s. l.) adopted by Persoon (Synopsis
       methodica fungorum, 31 December 1801) and names of other fungi
       (excluding slime moulds) adopted by Fries (Systema mycologicum,
       vol. 1 (1 January 1821) to 3, with additional Index (1832), and Elen-
       chus fungorum, vol. 1-2), are sanctioned (see Art. 15). For nomencla-
       tural purposes names given to lichens shall be considered as applying
       to their fungal component.

(e)   Algae, 1 May 1753 (Linnaeus, Species plantarum, ed. 1). Exceptions:

       Nostocaceae homocysteae, 1 January 1892 (Gomont, “Monogra-
       phie des Oscillariées”, in Ann. Sci. Nat., Bot., ser. 7, 15: 263-368; 16:
       91-264). The two parts of Gomont’s “Monographie”, which appeared
       in 1892 and 1893, respectively, are treated as having been published
       simultaneously on 1 January 1892.

       Nostocaceae heterocysteae, 1 January 1886 (Bornet & Flahault,
       “Révision des Nostocacées hétérocystées”, in Ann. Sci. Nat., Bot., ser.
       7, 3: 323-381; 4: 343-373; 5: 51-129; 7: 177-262). The four parts of
       the “Révision”, which appeared in 1886, 1886, 1887, and 1888, re-
       spectively, are treated as having been published simultaneously on
       1 January 1886.

       Desmidiaceae (s. l.), 1 January 1848 (Ralfs, British Desmidieae).

       Oedogoniaceae, 1 January 1900 (Hirn, “Monographie und Icono-
       graphie der Oedogoniaceen”, in Acta Soc. Sci. Fenn. 27(1)).

Fossil plants:

(f)   All groups, 31 December 1820 (Sternberg, Flora der Vorwelt, Ver-
       such 1: 1-24, t. 1-13). Schlotheim’s Petrefactenkunde (1820) is re-
       garded as published before 31 December 1820.

13.2.  The group to which a name is assigned for the purposes of this Arti-
cle is determined by the accepted taxonomic position of the type of the
name.

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Ex. 1.  The genus Porella and its single species, P. pinnata, were referred by Linnaeus
(1753) to the Musci; since the type specimen of P. pinnata is now accepted as belonging to
the Hepaticae, the names were validly published in 1753.

Ex. 2.  The designated type of Lycopodium L. (1753) is L. clavatum L. (1753) and the type
specimen of this is currently accepted as a pteridophyte. Accordingly, although the genus
is listed by Linnaeus among the Musci, the generic name and the names of the pterido-
phyte species included by Linnaeus under it were validly published in 1753.

13.3.  For nomenclatural purposes, a name is treated as pertaining to a
non-fossil taxon unless its type is fossil in origin. Fossil material is distin-
guished from non-fossil material by stratigraphic relations at the site of
original occurrence. In cases of doubtful stratigraphic relations, provisions
for non-fossil taxa apply.

13.4.  Generic names which appear in Linnaeus’s Species plantarum, ed. 1
(1753) and ed. 2 (1762-1763), are associated with the first subsequent de-
scription given under those names in Linnaeus’s Genera plantarum, ed. 5
(1754) and ed. 6 (1764). The spelling of the generic names included in
Species plantarum, ed. 1, is not to be altered because a different spelling
has been used in Genera plantarum, ed. 5.

13.5.  The two volumes of Linnaeus’s Species plantarum, ed. 1 (1753),
which appeared in May and August, 1753, respectively, are treated as
having been published simultaneously on 1 May 1753.

Ex. 3.  The generic names Thea L. (Sp. Pl.: 515. 24 Mai 1753), and Camellia L. (Sp. Pl.:
698. 16 Aug 1753; Gen. Pl., ed. 5: 311. 1754), are treated as having been published simul-
taneously on 1 May 1753. Under Art. 11.5 the combined genus bears the name Camellia,
since Sweet (Hort. Suburb. Lond.: 157. 1818), who was the first to unite the two genera,
chose that name, and cited Thea as a synonym.

13.6.  Names of anamorphs of fungi with a pleomorphic life cycle do not,
irrespective of priority, affect the nomenclatural status of the names of the
correlated holomorphs (see Art. 59.4).

Article 14

14.1.  In order to avoid disadvantageous nomenclatural changes entailed
by the strict application of the rules, and especially of the principle of
priority in starting from the dates given in Art. 13, this Code provides, in
App. II and III, lists of names of families, genera, and species that are
conserved (nomina conservanda). Conserved names are legitimate even
though initially they may have been illegitimate.

14.2.  Conservation aims at retention of those names which best serve
stability of nomenclature (see Rec. 50E).

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14.3.  The application of both conserved and rejected names is determined
by nomenclatural types. The type of the specific name cited as the type of
a conserved generic name may, if desirable, be conserved and listed in
App. IIIA.

14.4.  A conserved name of a family or genus is conserved against all
other names in the same rank based on the same type (nomenclatural, i.e.
homotypic, synonyms, which are to be rejected) whether or not these are
cited in the corresponding list as rejected names, and against those names
based on different types (taxonomic, i.e. heterotypic, synonyms) that are
listed as rejected ¹. A conserved name of a species is conserved against all
names listed as rejected, and against all combinations based on the re-
jected names.

Note 1.  The Code does not provide for conservation of a name against itself, i.e.
against the same name with the same type but with a different place and date of
valid publication than is given in the relevant entry in App. II or III, and perhaps
with a different authorship (but see Art. 14.9).

Note 2.  A species name listed as conserved or rejected in App. IIIB may have
been published as the name of a new taxon, or as a combination based on an ear-
lier name. Rejection of a name based on an earlier name does not in itself pre-
clude the use of the earlier name since that name is not “a combination based on a
rejected name” (Art. 14.4).

Ex. 1.  Rejection of Lycopersicon lycopersicum (L.) H. Karst. in favour of L. esculentum
Mill. does not preclude the use of the homotypic Solanum lycopersicum L.

14.5.  When a conserved name competes with one or more names based
on different types and against which it is not explicitly conserved, the
earliest of the competing names is adopted in accordance with Art. 11, ex-
cept for some conserved family names (App. IIB), which are conserved
against unlisted names.

Ex. 2.  If Weihea Spreng. (1825) is united with Cassipourea Aubl. (1775), the combined
genus will bear the prior name Cassipourea, although Weihea is conserved and Cas-
sipourea is not.

Ex. 3.  If Mahonia Nutt. (1818) is united with Berberis L. (1753), the combined genus will
bear the prior name Berberis, although Mahonia is conserved and Berberis is not.

Ex. 4.  Nasturtium R. Br. (1812) was conserved only against the homonym Nasturtium
Mill. (1754) and the nomenclatural (homotypic) synonym Cardaminum Moench (1794);
consequently if reunited with Rorippa Scop. (1760) it must bear the name Rorippa.

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¹ The International code of zoological nomenclature and the International code of nomen-
  clature of bacteria use the terms “objective synonym” and “subjective synonym” for no-
  menclatural and taxonomic synonym, respectively.

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14.6.  When a name of a taxon has been conserved against an earlier name
based on a different type, the latter is to be restored, subject to Art. 11, if it
is considered the name of a taxon at the same rank distinct from that of the
nomen conservandum, except when the earlier rejected name is a homo-
nym of the conserved name.

Ex. 5.  The generic name Luzuriaga Ruiz & Pav. (1802) is conserved against the earlier
names Enargea Banks ex Gaertn. (1788) and Callixene Comm. ex Juss. (1789). If, how-
ever, Enargea is considered to be a separate genus, the name Enargea is retained for it.

14.7.  A rejected name, or a combination based on a rejected name, may
not be restored for a taxon which includes the type of the corresponding
conserved name.

Ex. 6.  Enallagma Baill. (1888) is conserved against Dendrosicus Raf. (1838), but not
against Amphitecna Miers (1868); if Enallagma and Amphitecna are united, the combined
genus must bear the name Amphitecna, although the latter is not explicitly conserved
against Dendrosicus.

14.8.  The listed type of a conserved name may not be changed except by
the procedure outlined in Art. 14.12.

Ex. 7.  Bullock & Killick (in Taxon 6: 239. 1957) published a proposal that the listed type
of Plectranthus L’Hér. be changed from P. punctatus (L. f.) L’Hér. to P. fruticosus L’Hér.
This proposal was approved by the appropriate Committees and by an International Bo-
tanical Congress.

14.9.  A name may be conserved with a different type from that desig-
nated by the author or determined by application of the Code (see also
Art. 10.4). Such a name may be conserved either from its place of valid
publication (even though the type may not then have been included in the
named taxon) or from a later publication by an author who did include the
type as conserved. In the latter case the original name and the name as
conserved are treated as if they were homonyms (Art. 53), whether or not
the name as conserved was accompanied by a description or diagnosis of
the taxon named.

Ex. 8.  Bromus sterilis L. (1753) has been conserved from its place of valid publication
even though its conserved type, a specimen (Hubbard 9045, E) collected in 1932, was not
originally included in Linnaeus’s species.

Ex. 9.  Protea L. (1753) did not include the conserved type of the generic name, P. cyna-
roides (L.) L. (1771), which in 1753 was placed in the genus Leucadendron. Protea was
therefore conserved from the 1771 publication, and Protea L. (1771), although not de-
signed to be a new generic name and still including the original type elements, is treated as
if it were a validly published homonym of Protea L. (1753).

14.10.  A conserved name, with any corresponding autonym, is conserved
against all earlier homonyms. An earlier homonym of a conserved name is

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not made illegitimate by that conservation but is unavailable for use; if not
otherwise illegitimate, it may serve as basionym of another name or com-
bination based on the same type (see also Art. 55.3).

Ex. 10.  The generic name Smithia Aiton (1789), conserved against Damapana Adans.
(1763), is thereby conserved automatically against the earlier homonym Smithia Scop.
(1777).

14.11.  A name may be conserved in order to preserve a particular spelling
or gender. A name so conserved is to be attributed without change of pri-
ority to the author who validly published it, not to an author who later
introduced the conserved spelling or gender.

Ex. 11.  The spelling Rhodymenia, used by Montagne (1839), has been conserved against
the original spelling Rhodomenia, used by Greville (1830). The name is to be cited as
Rhodymenia Grev. (1830).

Note 3.  The date of conservation does not affect the priority (Art. 11) of a con-
served name, which is determined only on the basis of the date of valid publica-
tion (Art. 32-45).

14.12.  The lists of conserved names will remain permanently open for
additions and changes. Any proposal of an additional name must be ac-
companied by a detailed statement of the cases both for and against its
conservation. Such proposals must be submitted to the General Committee
(see Div. III), which will refer them for examination to the committees for
the various taxonomic groups.

14.13.  Entries of conserved names may not be deleted.

14.14.  When a proposal for the conservation of a name, or of its rejection
under Art. 56, has been approved by the General Committee after study by
the Committee for the taxonomic group concerned, retention (or rejection)
of that name is authorized subject to the decision of a later International
Botanical Congress.

Recommendation 14A

14A.1.  When a proposal for the conservation of a name, or of its rejection under
Art. 56, has been referred to the appropriate Committee for study, authors should
follow existing usage as far as possible pending the General Committee’s rec-
ommendation on the proposal.

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Article 15

15.1.  Names sanctioned under Art. 13.1(d) are treated as if conserved
against earlier homonyms and competing synonyms. Such names, once
sanctioned, remain sanctioned even if elsewhere in the sanctioning works
the sanctioning author does not recognize them.

Ex. 1.  Agaricus ericetorum Fr. was accepted by Fries in Systema mycologicum (1821), but
later (1828) regarded by him as a synonym of A. umbelliferus L. and not included in his
Index (1832) as an accepted name. Nevertheless A. ericetorum is a sanctioned name.

15.2.  An earlier homonym of a sanctioned name is not made illegitimate
by that sanctioning but is unavailable for use; if not otherwise illegitimate,
it may serve as a basionym of another name or combination based on the
same type (see also Art. 55.3).

Ex. 2.  Patellaria Hoffm. (1789) is an earlier homonym of the sanctioned generic name
Patellaria Fr. (1822) : Fr.. Hoffmann’s name is legitimate but unavailable for use. Lecanidion
Endl. (1830), based on the same type as Patellaria Fr. : Fr., is illegitimate under Art. 52.1.

Ex. 3.  Agaricus cervinus Schaeff. (1774) is an earlier homonym of the sanctioned A.
cervinus Hoffm. (1789) : Fr.; Schaeffer’s name is unavailable for use, but it is legitimate
and may serve as basionym for combinations in other genera. In Pluteus Fr. the combina-
tion is cited as P. cervinus (Schaeff.) P. Kumm. and has priority over the taxonomic (hete-
rotypic) synonym P. atricapillus (Batsch) Fayod, based on A. atricapillus Batsch (1786).

15.3.  When, for a taxon from family to and including genus, two or more
sanctioned names compete, Art. 11.3 governs the choice of the correct
name (see also Art. 15.5).

15.4.  When, for a taxon below the rank of genus, two or more sanctioned
names and/or two or more names with the same final epithet and type as a
sanctioned name compete, Art. 11.4 governs the choice of the correct name.

Note 1.  The date of sanctioning does not affect the priority (Art. 11) of a sanc-
tioned name, which is determined only on the basis of valid publication. In par-
ticular, when two or more homonyms are sanctioned only the earliest of them
may be used, the later being illegitimate under Art. 53.2.

Ex. 4.  Fries (Syst. Mycol. 1: 41. 1821) accepted Agaricus flavovirens Pers. (1801), treat-
ing A. equestris L. (1753) as a synonym. Later (Elench. Fung. 1: 6. 1828) he stated “No-
men prius et aptius arte restituendum” and accepted A. equestris. Both names are sanct-
ioned, but when they are considered synonyms A. equestris, having priority, is to be used.

15.5.  A name which neither is sanctioned nor has the same type and final
epithet as a sanctioned name in the same rank may not be applied to a taxon
which includes the type of a sanctioned name in that rank the final epithet
of which is available for the required combination (see Art. 11.4(b)).

15.6.  Conservation (Art. 14) and explicit rejection (Art. 56.1) override
sanctioning.

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CHAPTER III. NOMENCLATURE OF TAXA ACCORDING TO

THEIR RANK

SECTION 1. NAMES OF TAXA ABOVE THE RANK OF FAMILY

Article 16

16.1.  The name of a taxon above the rank of family is treated as a noun in
the plural and is written with an initial capital letter. Such names may be
either (a) automatically typified names, formed by replacing the termina-
tion -aceae in a legitimate name of an included family based on a generic
name by the termination denoting their rank (preceded by the connecting
vowel -o- if the termination begins with a consonant), as specified in Rec.
16A.1-3 and Art. 17.1; or (b) descriptive names, not so formed, which
apply to taxa with a recognized circumscription and which may be used
unchanged at different ranks.

Ex. 1.  Automatically typified names above the rank of family: Magnoliophyta, based on
Magnoliaceae; Gnetophytina, based on Gnetaceae; Pinopsida, based on Pinaceae; Marat-
tiidae, based on Marattiaceae; Caryophyllidae and Caryophyllales, based on Caryophyl-
laceae; Fucales, based on Fucaceae; Bromeliineae, based on Bromeliaceae.

Ex. 2.  Descriptive names above the rank of family: Anthophyta, Chlorophyta, Parietales;
Ascomycota, Ascomycotina, Ascomycetes; Angiospermae, Centrospermae, Coniferae, Enan-
tioblastae, Gymnospermae.

16.2.  For automatically typified names, the name of the subdivision or
subphylum that includes the type of the adopted name of a division or
phylum, the name of the subclass that includes the type of the adopted
name of a class, and the name of the suborder that includes the type of the
adopted name of an order are to be based on the same type as the corre-
sponding higher-ranked name.

Ex. 3.  Pteridophyta Bergen & B. M. Davis (1906) and Pteridophytina B. Boivin (1956);
Gnetopsida Engl. (1898) and Gnetidae Cronquist & al. (1966); Liliales Perleb (1826) and
Liliineae Rchb. (1841).

16.3.  When an automatically typified name above the rank of family has
been published with an improper Latin termination, not agreeing with

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those provided for in Rec.16A.1-3 and Art. 17.1, the termination must be
changed to conform with these standards, without change of the author
citation or date of publication (see Art. 32.5). However, if such names are
published with a non-Latin termination they are not validly published.

Ex. 4.  “Cactarieae” (Dumortier, 1829, based on Cactaceae) and “Coriales” (Lindley,
1833, based on Coriariaceae), both published for taxa of the rank of order, are to be cor-
rected to Cactales Dumort. (1829) and Coriariales Lindl. (1833), respectively.

Ex. 5.  However, Acoroidées (Kirschleger, Fl. Alsace 2: 103. 1853 - Jul 1857), published
for a taxon of the rank of order, is not to be accepted as “Acorales Kirschl.”, as it has a
French rather than a Latin termination. The name Acorales was later validly published by
Reveal (in Phytologia 79: 72. 1996).

Note 1.  The terms “divisio” and “phylum”, and their equivalents in modern lan-
guages, are treated as referring to one and the same rank. When “divisio” and
“phylum” are used simultaneously to denote different ranks, this usage is contrary
to Art. 5, and the corresponding names are not validly published (Art. 33.7).

16.4.  Where one of the word elements -monad-, -cocc-, -nemat-, or -clad-,
being the genitive singular stem of the second part of a name of an in-
cluded genus, has been omitted before the termination -phyceae or -phyta,
the shortened class name or division or phylum name is regarded as based
on the generic name in question if such derivation is obvious or is indi-
cated at establishment of the group name.

Ex. 6.  The name Raphidophyceae Chadef. ex P. C. Silva (1980) was indicated by its
author to be based on Raphidomonas F. Stein (1878).

Note 2.  The principle of priority is not mandatory for names of taxa above the
rank of family (Art. 11.9); but see Rec. 16B).

Recommendation 16A

16A.1.  A name of a division or phylum should end in -phyta unless the taxon is a
division or phylum of fungi, in which case its name should end in -mycota.

16A.2.  A name of a subdivision or subphylum should end in -phytina, unless it is
a subdivision or subphylum of fungi, in which case it should end in -mycotina.

16A.3.  A name of a class or of a subclass should end as follows:

(a)  In the algae: -phyceae (class) and -phycidae (subclass);

(b)  In the fungi: -mycetes (class) and -mycetidae (subclass);

(c)  In other groups of plants: -opsida (class) and -idae, but not -viridae
       (subclass).

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Recommendation 16B

16B.1.  In choosing among typified names for a taxon above the rank of family,
authors should generally follow the principle of priority.

Article 17

17.1.  Automatically typified names of orders or suborders are to end in
-ales (but not -virales) and -ineae, respectively.

17.2.  Names intended as names of orders, but published with their rank
denoted by a term such as “cohors”, “nixus”, “alliance”, or “Reihe” in-
stead of “order”, are treated as having been published as names of orders.

Recommendation 17A

17A.1.  Authors should not publish new names for orders that include a family
from the name of which an existing ordinal name is derived.

SECTION 2. NAMES OF FAMILIES AND SUBFAMILIES, TRIBES AND

SUBTRIBES

Article 18

18.1.  The name of a family is a plural adjective used as a noun; it is
formed from the genitive singular of a legitimate name of an included
genus by replacing the genitive singular inflection (Latin -ae, -i, -us, -is;
transliterated Greek -ou, -os, -es, -as, or -ous, including the latter’s
equivalent -eos) with the termination -aceae (but see Art.18.5). For ge-
neric names of non-classical origin, when analogy with classical names is
insufficient to determine the genitive singular, -aceae is added to the full
word. For generic names with alternative genitives the one implicitly used
by the original author must be maintained.

Ex. 1.  Family names based on a generic name of classical origin: Rosaceae (from Rosa,
Rosae), Salicaceae (from Salix, Salicis), Plumbaginaceae (from Plumbago, Plumbaginis),
Rhodophyllaceae (from Rhodophyllus, Rhodophylli), Rhodophyllidaceae (from Rhodo-
phyllis, Rhodophyllidos), Sclerodermataceae (from Scleroderma, Sclerodermatos), Aex-
toxicaceae (from Aextoxicon, Aextoxicou), Potamogetonaceae (from Potamogeton, Pota-
mogetonos).

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Ex. 2.  Family names based on a generic name of non-classical origin: Nelumbonaceae
(from Nelumbo, Nelumbonis, declined by analogy with umbo, umbonis), Ginkgoaceae
(from Ginkgo, indeclinable).

18.2.  Names intended as names of families, but published with their rank
denoted by one of the terms “order” (ordo) or “natural order” (ordo natu-
ralis) instead of “family”, are treated as having been published as names
of families (see also Art. 19.2).

Ex. 3.  Cyperaceae Juss. (1789), Lobeliaceae Juss. (1813), and Xylomataceae Fr. (1820)
were published as “ordo Cyperoideae”, “ordo naturalis Lobeliaceae”, and “ordo Xylo-
maceae”, respectively.

18.3.  A name of a family based on an illegitimate generic name is ille-
gitimate unless conserved. Contrary to Art. 32.1(b) such a name is validly
published if it complies with the other requirements for valid publication.

Ex. 4.  Caryophyllaceae Juss., nom. cons. (from Caryophyllus Mill. non L.); Winteraceae
R. Br. ex Lindl., nom. cons. (from Wintera Murray, an illegitimate synonym of Drimys J.
R. Forst. & G. Forst.).

18.4.  When a name of a family has been published with an improper
Latin termination, the termination must be changed to conform with the
rule, without change of the author citation or date of publication (see Art.
32.5). However, if such a name is published with a non-Latin termination,
it is not validly published.

Ex. 5.  “Coscinodisceae” (Kützing 1844), published to designate a family, is to be accepted
as Coscinodiscaceae Kütz. 1844 and not attributed to De Toni, who first used the correct
spelling (in Notarisia 5: 915. 1890).

Ex. 6.  “Atherospermeae” (Brown 1814), published to designate a family, is to be accepted
as Atherospermataceae R. Br. and not attributed to Airy Shaw (in Willis, Dict. Fl. Pl.,
ed. 7: 104. 1966), who first used the correct spelling, or to Lindley (Veg. Kingd.: 300.
1846), who used the spelling “Atherospermaceae”.

Ex. 7.  However, Tricholomées (Roze in Bull. Soc. Bot. France 23: 49. 1876), published to
designate a family, is not to be accepted as “Tricholomataceae Roze”, as it has a French
rather than a Latin termination. The name Tricholomataceae was later validated by Pouzar
(1983; see App. IIA).

18.5.  The following names, of long usage, are treated as validly pub-
lished: Palmae (Arecaceae; type, Areca L.); Gramineae (Poaceae; type,
Poa L.); Cruciferae (Brassicaceae; type, Brassica L.); Leguminosae (Fa-
baceae; type, Faba Mill. [= Vicia L.]); Guttiferae (Clusiaceae; type, Clu-
sia L.); Umbelliferae (Apiaceae; type, Apium L.); Labiatae (Lamiaceae;
type, Lamium L.); Compositae (Asteraceae; type, Aster L.). When the Pa-
pilionaceae (Fabaceae; type, Faba Mill.) are regarded as a family distinct

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from the remainder of the Leguminosae, the name Papilionaceae is con-
served against Leguminosae.

18.6.  The use, as alternatives, of the family names indicated in parenthe-
ses in Art. 18.5 is authorized.

Article 19

19.1.  The name of a subfamily is a plural adjective used as a noun; it is
formed in the same manner as the name of a family (Art. 18.1) but by
using the termination -oideae instead of -aceae.

19.2.  Names intended as names of subfamilies, but published with their
rank denoted by the term “suborder” (subordo) instead of subfamily, are
treated as having been published as names of subfamilies (see also Art.
18.2).

19.3.  A tribe is designated in a similar manner, with the termination -eae,
and a subtribe similarly with the termination -inae (but not -virinae).

19.4.  The name of any subdivision of a family that includes the type of
the adopted, legitimate name of the family to which it is assigned is to be
based on the generic name equivalent to that type (but see Art. 19.7).

Ex. 1.  The type of the family name Rosaceae Adans. is Rosa L. and hence the subfamily
and tribe which include Rosa are to be called Rosoideae Endl. and Roseae DC.

Ex. 2.  The type of the family name Poaceae Barnhart (nom. alt., Gramineae Adans. – see
Art. 18.5) is Poa L. and hence the subfamily and tribe which include Poa are to be called
Pooideae Asch. and Poëae R. Br.

Note 1.  This provision applies only to the names of those subordinate taxa that
include the type of the adopted name of the family (but see Rec. 19A.2).

Ex. 3.  The subfamily including the type of the family name Ericaceae Juss. (Erica L.),
irrespective of priority, is to be called Ericoideae Endl., and the tribe including this type is
called Ericeae D. Don. However, the correct name of the tribe including both Rhododen-
dron L., the type of the subfamily name Rhododendroideae Endl., and Rhodora L. is Rho-
doreae D. Don (1834) not Rhododendreae Brongn. (1843).

Ex. 4.  The subfamily of the family Asteraceae Martinov (nom. alt., Compositae Adans.)
including Aster L., the type of the family name, is irrespective of priority to be called
Asteroideae Asch., and the tribe and subtribe including Aster are to be called Astereae
Cass. and Asterinae Less., respectively. However, the correct name of the tribe including
both Cichorium L., the type of the subfamily name Cichorioideae W. D. J. Koch (1837),
and Lactuca L. is Lactuceae Cass. (1815), not Cichorieae D. Don (1829), while that of the
subtribe including both Cichorium and Hyoseris L. is Hyoseridinae Less. (1832), not
Cichoriinae Sch. Bip. (1841) (unless the Cichoriaceae Juss. are accepted as a family dis-
tinct from Compositae).

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19.5.  A name of a subdivision of a family based on an illegitimate generic
name that is not the base of a conserved family name is illegitimate. Con-
trary to Art. 32.1(b) such a name is validly published if it complies with
the other requirements for valid publication.

Ex. 5.  The name Caryophylloideae Arn. (1832), based on Caryophyllaceae Juss., nom.
cons., is legitimate although it is ultimately based on the illegitimate Caryophyllus Mill.
non L.

19.6.  When a name of a taxon assigned to one of the above categories has
been published with an improper Latin termination, such as -eae for a
subfamily or -oideae for a tribe, the termination must be changed to ac-
cord with the rule, without change of the author citation or date of publi-
cation (see Art. 32.5). However, if such names are published with a non-
Latin termination they are not validly published.

Ex. 6.  “Climacieae” (Grout, Moss Fl. N. Amer. 3: 4. 1928), published to designate a sub-
family, is to be changed to Climacioideae Grout (1928).

Ex. 7.  However, Melantheen (Kittel in Richard, Nouv. Elém. Bot., ed. 3, Germ. Transl.:
727. 1840), published to designate a tribe, is not to be accepted as “Melanthieae Kitt.”, as it
has a German rather than a Latin termination. The name Melanthieae was validated later
by Grisebach (Spic. Fl. Rumel. 2: 377. 1846).

19.7.  When the Papilionaceae are included in the family Leguminosae
(nom. alt., Fabaceae; see Art. 18.5) as a subfamily, the name Papilionoi-
deae may be used as an alternative to Faboideae.

Recommendation 19A

19A.1.  When a family is changed to the rank of a subdivision of a family, or the
inverse change occurs, and no legitimate name is available in the new rank, the
name should be retained, and only its termination (-aceae, -oideae, -eae, -inae)
altered.

Ex. 1.  The subtribe Drypetinae Griseb. (1859) (Euphorbiaceae) when raised to the rank of
tribe was named Drypeteae Hurus. (1954); the subtribe Antidesmatinae Müll. Arg. (1865)
(Euphorbiaceae) when raised to the rank of subfamily was named Antidesmatoideae
Hurus. (1954).

19A.2.  When a subdivision of a family is changed to another such rank, and no
legitimate name is available in the new rank, its name should be based on the
same generic name as the name in the former rank.

Ex. 2.  Three tribes of the family Ericaceae, none of which includes the type of that family
name (Erica L.), are Pyroleae D. Don, Monotropeae D. Don, and Vaccinieae D. Don. The
later names Pyroloideae A. Gray, Monotropoideae A. Gray, and Vaccinioideae Endl. are
based on the same generic names.

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SECTION 3. NAMES OF GENERA AND SUBDIVISIONS OF GENERA

Article 20

20.1.  The name of a genus is a noun in the nominative singular, or a word
treated as such, and is written with an initial capital letter (see Art. 60.2).
It may be taken from any source whatever, and may even be composed in
an absolutely arbitrary manner, but it must not end in -virus.

Ex. 1.  Rosa, Convolvulus, Hedysarum, Bartramia, Liquidambar, Gloriosa, Impatiens,
Rhododendron, Manihot, Ifloga (an anagram of Filago).

20.2.  The name of a genus may not coincide with a technical term cur-
rently used in morphology unless it was published before 1 January 1912
and accompanied by a specific name published in accordance with the
binary system of Linnaeus.

Ex. 2.  “Radicula” (Hill, 1756) coincides with the technical term “radicula” (radicle) and
was not accompanied by a specific name in accordance with the binary system of Lin-
naeus. The name Radicula is correctly attributed to Moench (1794), who first combined it
with specific epithets.

Ex. 3.  Tuber F. H. Wigg. : Fr., when published in 1780, was accompanied by a binary
specific name (Tuber gulosorum F. H. Wigg.) and is therefore validly published.

Ex. 4.  The intended generic names “Lanceolatus” (Plumstead, 1952) and “Lobata”
(Chapman, 1952) coincide with technical terms and are therefore not validly published.

Ex. 5.  Words such as “radix”, “caulis”, “folium”, “spina”, etc., cannot now be validly
published as generic names.

20.3.  The name of a genus may not consist of two words, unless these
words are joined by a hyphen.

Ex. 6.  “Uva ursi”, as originally published by Miller (1754), consisted of two separate
words unconnected by a hyphen, and is therefore not validly published (Art. 32.1(b)); the
name is correctly attributed to Duhamel (1755) as Uva-ursi (hyphenated when published).

Ex. 7.  However, names such as Quisqualis L. (formed by combining two words into one
when originally published), Sebastiano-schaueria Nees, and Neves-armondia K. Schum.
(both hyphenated when originally published) are validly published.

Note 1.  The names of intergeneric hybrids are formed according to the provisions
of Art. H.6.

20.4.  The following are not to be regarded as generic names:

(a)  Words not intended as names.

Ex. 8.  The designation “Anonymos” was applied by Walter (Fl. Carol.: 2, 4, 9, etc. 1788)
to 28 different genera to indicate that they were without names.

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Ex. 9.  “Schaenoides” and “Scirpoides”, as used by Rottbøll (Descr. Pl. Rar. Progr.: 14,
27. 1772) to indicate unnamed genera resembling Schoenus and Scirpus which he stated
(on p. 7) he intended to name later, are token words and not generic names. These un-
named genera were later legitimately named Kyllinga Rottb. and Fuirena Rottb.

(b)  Unitary designations of species.

Note 2.  Examples such as “Leptostachys” and “Anthopogon”, listed in pre-
Tokyo editions of the Code, were from publications now listed in App. V.

Recommendation 20A

20A.1.  Authors forming generic names should comply with the following advice:

(a)   To use Latin terminations insofar as possible.

(b)   To avoid names not readily adaptable to the Latin language.

(c)   Not to make names which are very long or difficult to pronounce in Latin.

(d)   Not to make names by combining words from different languages.

(e)   To indicate, if possible, by the formation or ending of the name the affinities
       or analogies of the genus.

(f)   To avoid adjectives used as nouns.

(g)   Not to use a name similar to or derived from the epithet in the name of one of
       the species of the genus.

(h)   Not to dedicate genera to persons quite unconnected with botany or at least
       with natural science.

(i)   To give a feminine form to all personal generic names, whether they com-
       memorate a man or a woman (see Rec. 60B).

(j)   Not to form generic names by combining parts of two existing generic
       names, because such names are likely to be confused with nothogeneric
       names (see Art. H.6).

Ex. 1.  Hordelymus (K. Jess.) K. Jess. is based on Hordeum subg. Hordelymus K. Jess. The
subgeneric epithet was formed by combining parts of the generic names Hordeum L. and
Elymus L. (see also Art. H.3 Ex. 2).

Article 21

21.1.  The name of a subdivision of a genus is a combination of a generic
name and a subdivisional epithet. A connecting term (subgenus, sectio,
series, etc.) is used to denote the rank.

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21.2.  The epithet is either of the same form as a generic name, or a noun
in the genitive plural, or a plural adjective agreeing in gender with the
generic name, but not noun in the genitive singular. It is written with an
initial capital letter (see Art. 32.5 and 60.2).

21.3.  The epithet in the name of a subdivision of a genus is not to be
formed from the name of the genus to which it belongs by adding the pre-
fix Eu-.

Ex. 1.  Costus subg. Metacostus; Ricinocarpos sect. Anomodiscus; Valeriana sect. Valeri-
anopsis; Euphorbia sect. Tithymalus; Pleione subg. Scopulorum; Euphorbia subsect. Te-
nellae; Sapium subsect. Patentinervia; Arenaria ser. Anomalae; but not Carex sect. “Eu-
carex”.

Note 1.  Names of subdivisions of the same genus, even if they differ in rank, are
homonyms if they have the same epithet but are based on different types (Art.
53.4).

Note 2.  The names of hybrids with the rank of a subdivision of a genus are formed
according to the provisions of Art. H.7.

21.4.  The use of a binary combination instead of a subdivisional epithet is not
admissible. Contrary to Art. 32.1(b), names so constructed are validly pub-
lished but are to be altered to the proper form without change of author cita-
tion or date of publication.

Ex. 2.  Sphagnum “b. Sph. rigida” (Lindberg in Öfvers. Förh. Kongl. Svenska Vetensk.-
Akad. 19: 135. 1862) and S. sect. “Sphagna rigida” (Limpricht, Laubm. Deutschl. 1: 116.
1885) are to be cited as Sphagnum [unranked] Rigida Lindb. and S. sect. Rigida (Lindb.)
Limpr., respectively.

Recommendation 21A

21A.1.  When it is desired to indicate the name of a subdivision of the genus to
which a particular species belongs in connection with the generic name and spe-
cific epithet, the subdivisional epithet should be placed in parentheses between
the two; when desirable, the subdivisional rank may also be indicated.

21A.1.  Astragalus (Cycloglottis) contortuplicatus; A. (Phaca) umbellatus; Loranthus (sect.
Ischnanthus) gabonensis.

Recommendation 21B

21B.1.  The epithet in the name of a subgenus or section is preferably a noun,
that in the name of a subsection or lower subdivision of a genus preferably a
plural adjective.

21B.2.  Authors, when proposing new epithets for names of subdivisions of
genera, should avoid those in the form of a noun when other co-ordinate

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subdivisions of the same genus have them in the form of a plural adjective, and
vice-versa. They should also avoid, when proposing an epithet for a name of a
subdivision of a genus, one already used for a subdivision of a closely related
genus, or one which is identical with the name of such a genus.

21B.3.  When a section or a subgenus is raised to the rank of genus, or the inverse
change occurs, the original name or epithet should be retained unless the resulting
name would be contrary to this Code.

Article 22

22.1.  The name of any subdivision of a genus that includes the type of the
adopted, legitimate name of the genus to which it is assigned is to repeat
that generic name unaltered as its epithet, not followed by an author cita-
tion (see Art. 46). Such names are termed autonyms (Art. 6.8; see also
Art. 7.6).

Note 1.  This provision applies only to the names of those subordinate taxa that
include the type of the adopted name of the genus (but see Rec. 22A).

22.2.  A name of a subdivision of a genus that includes the type (i.e. the
original type or all elements eligible as type or the previously designated
type) of the adopted, legitimate name of the genus is not validly published
unless its epithet repeats the generic name unaltered. For the purposes of
this provision, explicit indication that the nomenclaturally typical element
is included is considered as equivalent to inclusion of the type, whether or
not it has been previously designated (see also Art. 21.3).

Ex. 1.  “Dodecatheon sect. Etubulosa” (Knuth in Engler, Pflanzenr. 22: 234. 1905) was
not validly published since it was proposed for a section that included D. meadia L., the
original type of the generic name Dodecatheon L.

Ex. 2.  Cactus [unranked] Melocactus L. (Gen. Pl., ed. 5: 210. 1754) was proposed for one
of four unranked (Art. 35.3), named subdivisions of the genus Cactus, comprising C. me-
locactus L. (its type under Art. 22.6) and C. mammillaris L. It is validly published, even
though C. melocactus was subsequently designated as the type of Cactus L. (by Britton &
Millspaugh, Bahama Fl.: 294. 1920) and, later still, C. mammillaris became the conserved
type of the generic name (by the way in which the family name Cactaceae Juss. was con-
served).

22.3.  The first instance of valid publication of a name of a subdivision of
a genus under a legitimate generic name automatically establishes the
corresponding autonym (see also Art. 11.6 and 32.6).

Ex. 3.  The subgenus of Malpighia L. that includes the lectotype of the generic name
(M. glabra L.) is called M. subg. Malpighia, not M. subg. Homoiostylis Nied.; and the
section of Malpighia including the lectotype of the generic name is called M. sect. Malpi-
ghia, not M. sect. Apyrae DC.

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Ex. 4.  However, the correct name of the section of the genus Rhododendron L. that
includes R. luteum Sweet, the type of R. subg. Anthodendron (Rchb.) Rehder, is R. sect.
Pentanthera G. Don, the oldest legitimate name for the section, and not R. sect. Anthoden-
dron.

22.4.  The epithet in the name of a subdivision of a genus may not repeat
unchanged the correct name of the genus, unless the two names have the
same type.

22.5.  The epithet in the name of a subdivision of a genus may not repeat
the generic name unaltered if the latter is illegitimate.

22.6.  When the epithet in the name of a subdivision of a genus is identical
with or derived from the epithet of one of its constituent species, the type
of the name of the subdivision of the genus is the same as that of the spe-
cies name, unless the original author of the subdivisional name designated
another type.

Ex. 5.  The type of Euphorbia subg. Esula Pers. is E. esula L.; the designation of E. peplus
L. as lectotype by Croizat (in Revista Sudamer. Bot. 6: 13. 1939) has no standing.

22.7.  When the epithet in the name of a subdivision of a genus is identical
with or derived from the epithet in a specific name that is a later homo-
nym, its type is the type of that later homonym, the correct name of which
necessarily has a different epithet.

Recommendation 22A

22A.1.  A section including the type of the correct name of a subgenus, but not
including the type of the correct name of the genus, should, where there is no
obstacle under the rules, be given a name with the same epithet and type as the
subgeneric name.

22A.2.  A subgenus not including the type of the correct name of the genus
should, where there is no obstacle under the rules, be given a name with the same
epithet and type as the correct name of one of its subordinate sections.

Ex. 1.  Instead of using a new epithet at the subgeneric level, Brizicky raised Rhamnus
sect. Pseudofrangula Grubov to the rank of subgenus as R. subg. Pseudofrangula (Grubov)
Brizicky. The type of both names is the same, R. alnifolia L’Hér.

SECTION 4. NAMES OF SPECIES

Article 23

23.1.  The name of a species is a binary combination consisting of the
name of the genus followed by a single specific epithet in the form of an

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adjective, a noun in the genitive, or a word in apposition, or several words,
but not a phrase name of one or more descriptive nouns and associated
adjectives in the ablative (see Art. 23.6(a)), nor certain other irregularly
formed designations (see Art. 23.6(c)). If an epithet consists of two or
more words, these are to be united or hyphenated. An epithet not so joined
when originally published is not to be rejected but, when used, is to be
united or hyphenated, as specified in Art. 60.9.

23.2.  The epithet in the name of a species may be taken from any source
whatever, and may even be composed arbitrarily (but see Art. 60.1).

Ex. 1.  Cornus sanguinea, Dianthus monspessulanus, Papaver rhoeas, Uromyces fabae,
Fumaria gussonei, Geranium robertianum, Embelia sarasiniorum, Atropa bella-donna,
Impatiens noli-tangere, Adiantum capillus-veneris, Spondias mombin (an indeclinable
epithet).

23.3.  Symbols forming part of specific epithets proposed by Linnaeus do
not invalidate the relevant names but must be transcribed.

Ex. 2.  Scandix pecten ♀ L. is to be transcribed as Scandix pecten-veneris; Veronica ana-
gallis ∇ L. is to be transcribed as Veronica anagallis-aquatica.

23.4.  The specific epithet, with or without the addition of a transcribed
symbol, may not exactly repeat the generic name (such repetition would
result in a tautonym).

Ex. 3.  “Linaria linaria” and “Nasturtium nasturtium-aquaticum” are contrary to this rule
and cannot be validly published.

Ex. 4.  Linum radiola L. (1753) when transferred to Radiola Hill may not be named “Ra-
diola radiola”, as was done by Karsten (1882), since that combination is invalid (see Art.
32.1(b)). The next oldest name, L. multiflorum Lam. (1779), is illegitimate, being a super-
fluous name for L. radiola. Under Radiola, the species has been given the legitimate name
R. linoides Roth (1788).

23.5.  The specific epithet, when adjectival in form and not used as a
noun, agrees grammatically with the generic name; when it is a noun in
apposition or a genitive noun, it retains its own gender and termination
irrespective of the gender of the generic name. Epithets not conforming to
this rule are to be corrected (see Art. 32.5). In particular, the usage of the
word element -cola as an adjective is a correctable error.

Ex. 5.  Adjectival epithets: Helleborus niger L., Brassica nigra (L.) W. D. J. Koch, Ver-
bascum nigrum L.; Vinca major L., Tropaeolum majus L.; Peridermium balsameum Peck,
derived from the epithet of Abies balsamea (L.) Mill., treated as an adjective.

Ex. 6.  Names with a noun for an epithet: Lythrum salicaria L., Convolvulus cantabrica L.,
Gentiana pneumonanthe L., all with epithets featuring pre-Linnaean generic names.

Gloeosporium balsameae Davis, derived from the epithet of Abies balsamea (L.) Mill.,
treated as a noun.

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Ex. 7.  Correctable errors: The epithet of Polygonum segetum Kunth (1817) is a genitive
plural noun (of the corn fields); the combination Persicaria “segeta”, proposed by Small,
is a correctable error for Persicaria segetum (Kunth) Small (1903).  –  In Masdevallia
echidna Rchb. f. (1855), the epithet corresponds to the generic name of an animal; upon
transfer to Porroglossum Schltr., the combination P. “echidnum” was proposed by Garay,
which is a correctable error for P. echidna (Rchb. f.) Garay (1953).

Ex. 8.  Rubus “amnicolus” is a correctable error for R. amnicola Blanch. (1906).

23.6.  The following designations are not to be regarded as specific names:

(a)  Descriptive designations consisting of a generic name followed by a
       phrase name (Linnaean “nomen specificum legitimum”) of one or
       more descriptive nouns and associated adjectives in the ablative.

Ex. 9.  Smilax “caule inermi” (Aublet, Hist. Pl. Guiane 2, Tabl.: 27. 1775) is an abbrevi-
ated descriptive reference to an imperfectly known species which is not given a binomial
in the text but referred to merely by a phrase name cited from Burman.

(b)  Other designations of species consisting of a generic name followed
       by one or more words not intended as a specific epithet.

Ex. 10.  Viola “qualis” (Krocker, Fl. Siles. 2: 512, 517. 1790); Urtica “dubia?” (Forsskål,
Fl. Aegypt.-Arab.: cxxi. 1775), the word “dubia?” being repeatedly used in Forsskål’s
work for species which could not be reliably identified.

Ex. 11.  Atriplex “nova” (Winterl, Index Hort. Bot. Univ. Hung.: fol. A [8] recto et verso.
1788), the word “nova” (new) being here used in connection with four different species of
Atriplex. However, in Artemisia nova A. Nelson (in Bull. Torrey Bot. Club 27: 274. 1900),
nova was intended as a specific epithet, the species having been newly distinguished from
others.

Ex. 12.  Cornus “gharaf” (Forsskål, Fl. Aegypt.-Arab.: xci, xcvi. 1775) is an interim des-
ignation not intended as a species name. An interim designation in Forsskål’s work is an
original designation (for an accepted taxon and thus not a “provisional name” as defined in
Art. 34.1(b)) with an epithet-like vernacular which is not used as an epithet in the “Centu-
riae” part of the work. Elcaja “roka” (Forsskål, Fl. Aegypt.-Arab.: xcv. 1775) is another
example of such an interim designation; in other parts of the work (p. c, cxvi, 127) this
species is not named.

Ex. 13.  In Agaricus “octogesimus nonus” and Boletus “vicesimus sextus” (Schaeffer,
Fung. Bavar. Palat. Nasc. 1: t. 100. 1762; 2: t. 137. 1763), the generic names are followed
by ordinal adjectives used for enumeration. The corresponding species were given valid
names, A. cinereus Schaeff. and B. ungulatus Schaeff., in the final volume of the same
work (1774).

Ex. 14.  Honckeny (1782; see Art. 46 Ex. 27) used species designations such as, in
Agrostis, “A. Reygeri I.”, A. Reyg. II.”, “A. Reyg. III.” (all referring to species described but
not named in Reyger, Tent. Fl. Gedan.: 36-37. 1763), and also “A. alpina. II” for a newly
described species following after A. alpina Scop. These are informal designations used for
enumeration, not validly published binomials; they may not be expanded into, e.g., “Agro-
stis reygeri-prima”.

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(c)  Designations of species consisting of a generic name followed by two
       or more adjectival words in the nominative case.

Ex. 15.  Salvia “africana coerulea” (Linnaeus, Sp. Pl.: 26. 1753) and Gnaphalium “fruti-
cosum flavum” (Forsskål, Fl. Aegypt.-Arab.: cxix. 1775) are generic names followed by
two adjectival words in the nominative case. They are not to be regarded as species names.

Ex. 16.  However, Rhamnus “vitis idaea” Burm. f. (Fl. Ind.: 61. 1768) is to be regarded as
a species name, since the generic name is followed by a noun and an adjective, both in the
nominative case; these words are to be hyphenated (R. vitis-idaea) under the provisions of
Art. 23.1 and Art. 60.9. In Anthyllis “Barba jovis” L. (Sp. Pl.: 720. 1753) the generic name
is followed by nouns in the nominative and in the genitive case, respectively, and they are
to be hyphenated (A. barba-jovis). Likewise, Hyacinthus “non scriptus” L. (Sp. Pl.: 316.
1753), where the generic name is followed by a negative particle and a past participle used
as an adjective, is corrected to H. non-scriptus, and Impatiens “noli tangere” L. (Sp. Pl.:
938. 1753), where the generic name is followed by two verbs, is corrected to I. noli-tan-
gere.

Ex. 17.  Similarly, in Narcissus “Pseudo Narcissus” L. (Sp. Pl.: 289. 1753) the generic
name is followed by an independent prefix and a noun in the nominative case, and the
name is to be corrected to N. pseudonarcissus under the provisions of Art. 23.1 and Art.
60.9.

(d)  Formulae designating hybrids (see Art. H.10.3).

23.7.  Phrase names used by Linnaeus as specific epithets (“nomina trivia-
lia”) are to be corrected in accordance with later usage by Linnaeus him-
self.

Ex. 18.  Apocynum “fol. [foliis] androsaemi” L. is to be cited as A. androsaemifolium L.
(Sp. Pl.: 213. 1753 [corr. L., Syst. Nat., ed. 10, 2: 946. 1759]); and Mussaenda “fr. [fructu]
frondoso” L., as M. frondosa L. (Sp. Pl.: 177. 1753 [corr. L., Syst. Nat., ed. 10, 2: 931.
1759]).

23.8.  Where the status of a designation of a species is uncertain under
Art. 23.6, established custom is to be followed (Pre. 10).

*Ex. 19.  Polypodium “F. mas”, P. “F. femina”, and P. “F. fragile” (Linnaeus, Sp. Pl.:
1090-1091. 1753) are, in accordance with established custom, to be treated as P. filix-mas
L., P. filix-femina L., and P. fragile L., respectively. Likewise, Cambogia “G. gutta” is to
be treated as C. gummi-gutta L. (Gen. Pl.: [522]. 1754). The intercalations “Trich.”
[Trichomanes] and “M.” [Melilotus] in the names of Linnaean species of Asplenium and
Trifolium, respectively, are to be deleted, so that names in the form Asplenium “Trich.
dentatum” and Trifolium “M. indica”, for example, are treated as A. dentatum L. and T.
indicum L. (Sp. Pl.: 765, 1080. 1753).

Recommendation 23A

23A.1.  Names of persons and also of countries and localities used in specific
epithets should take the form of nouns in the genitive (clusii, porsildiorum, sa-
harae) or of adjectives (clusianus, dahuricus) (see also Art. 60, Rec. 60C and D).

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23A.2.  The use of the genitive and the adjectival form of the same word to desig-
nate two different species of the same genus should be avoided (e.g. Lysimachia
hemsleyana Oliv. and L. hemsleyi Franch.).

23A.3.  In forming specific epithets, authors should comply also with the follow-
ing suggestions:

(a)  To use Latin terminations insofar as possible.

(b)  To avoid epithets which are very long and difficult to pronounce in Latin.

(c)  Not to make epithets by combining words from different languages.

(d)  To avoid those formed of two or more hyphenated words.

(e)  To avoid those which have the same meaning as the generic name (pleo-
       nasm).

(f)  To avoid those which express a character common to all or nearly all the
       species of a genus.

(g)  To avoid in the same genus those which are very much alike, especially those
       which differ only in their last letters or in the arrangement of two letters.

(h)  To avoid those which have been used before in any closely allied genus.

(i)   Not to adopt epithets from unpublished names found in correspondence,
       travellers’ notes, herbarium labels, or similar sources, attributing them to
       their authors, unless these authors have approved publication (see Rec. 34A).

(j)   To avoid using the names of little-known or very restricted localities unless
       the species is quite local.

SECTION 5. NAMES OF TAXA BELOW THE RANK OF SPECIES

(INFRASPECIFIC TAXA)

Article 24

24.1.  The name of an infraspecific taxon is a combination of the name of
a species and an infraspecific epithet. A connecting term is used to denote
the rank.

Ex. 1.  Saxifraga aizoon subf. surculosa Engl. & Irmsch. This taxon may also be referred
to as Saxifraga aizoon var. aizoon subvar. brevifolia f. multicaulis subf. surculosa Engl. &
Irmsch.; in this way a full classification of the subforma within the species is given, not
only its name.

24.2.  Infraspecific epithets are formed like specific epithets and, when
adjectival in form and not used as nouns, they agree grammatically with
the generic name (see Art. 32.5).

Ex. 2.  Solanum melongena var. insanum Prain (Bengal Pl.: 746. 1903, “insana”).

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24.3.  Infraspecific names with final epithets such as typicus, originalis,
originarius, genuinus, verus, and veridicus, purporting to indicate the
taxon containing the type of the name of the next higher taxon, are not
validly published unless they are autonyms (Art. 26).

Ex. 3.  Lobelia spicata “var. originalis” (McVaugh in Rhodora 38: 308. 1936) was not
validly published (see Art. 26 Ex. 1).

24.4.  The use of a binary combination instead of an infraspecific epithet
is not admissible. Contrary to Art. 32.1(b), names so constructed are val-
idly published but are to be altered to the proper form without change of
the author citation or date of publication.

Ex. 4.  Salvia grandiflora subsp. “S. willeana” (Holmboe in Bergens Mus. Skr., ser. 2,
1(2): 157. 1914) is to be cited as S. grandiflora subsp. willeana Holmboe.

Ex. 5.  Phyllerpa prolifera var. “Ph. firma” (Kützing, Sp. Alg.: 495. 1849) is to be altered
to P. prolifera var. firma Kütz.

Note 1.  Infraspecific taxa within different species may bear names with the same
final epithet; those within one species may bear names with the same final epithet
as the names of other species (but see Rec. 24B.1).

Ex. 6.  Rosa glutinosa var. leioclada H. Christ (in Boissier, Fl. Orient. Suppl.: 222. 1888)
and Rosa jundzillii f. leioclada Borbás (in Math. Term. Közlem. 16: 376, 383. 1880) are
both permissible, as is Viola tricolor var. hirta Ging. (in Candolle, Prodr. 1: 304. 1824), in
spite of the previous existence of a species named Viola hirta L.

Note 2.  Names of infraspecific taxa within the same species, even if they differ in
rank, are homonyms if they have the same epithet but are based on different types
(Art. 53.4).

Recommendation 24A

24A.1.  Recommendations made for forming specific epithets (Rec. 23A) apply
equally for infraspecific epithets.

Recommendation 24B

24B.1.  Authors proposing new infraspecific names should avoid epithets previ-
ously used as specific epithets in the same genus.

24B.2.  When an infraspecific taxon is raised to the rank of species, or the inverse
change occurs, the final epithet of its name should be retained unless the resulting
combination would be contrary to this Code.

Article 25

25.1.  For nomenclatural purposes, a species or any taxon below the rank
of species is regarded as the sum of its subordinate taxa, if any. In fungi, a
holomorph also includes its correlated form-taxa (see Art. 59).

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Ex. 1.  When Montia parvifolia (DC.) Greene is treated as comprising two subspecies, one
must write M. parvifolia subsp. parvifolia for that part of the species that includes the
nomenclatural type and excludes the type of the name of the other subspecies, M. parvi-
folia subsp. flagellaris (Bong.) Ferris. The name M. parvifolia applies to the species in its
entirety.

Article 26

26.1.  The name of any infraspecific taxon that includes the type of the
adopted, legitimate name of the species to which it is assigned is to repeat
the specific epithet unaltered as its final epithet, not followed by an author
citation (see Art. 46). Such names are termed autonyms (Art. 6.8; see also
Art. 7.6).

Ex. 1.  The variety which includes the type of the name Lobelia spicata Lam. is to be
named Lobelia spicata Lam. var. spicata (see also Art. 24 Ex. 3).

Note 1.  This provision applies only to the names of those subordinate taxa that
include the type of the adopted name of the species (but see Rec. 26A).

26.2.  A name of an infraspecific taxon that includes the type (i.e. the
holotype or all syntypes or the previously designated type) of the adopted,
legitimate name of the species to which it is assigned is not validly pub-
lished unless its final epithet repeats the specific epithet unaltered. For the
purpose of this provision, explicit indication that the nomenclaturally
typical element of the species is included is considered as equivalent to
inclusion of the type, whether or not it has been previously designated
(see also Art. 24.3).

Ex. 2.  The intended combination “Vulpia myuros subsp. pseudomyuros (Soy.-Will.) Maire
& Weiller” was not validly published in Maire (Fl. Afrique N. 3: 177. 1955) because it
included “F. myuros L., Sp. 1, p. 74 (1753) sensu stricto” in synonymy, Festuca myuros L.
being the basionym of Vulpia myuros (L.) C. C. Gmel.

Ex. 3.  Linnaeus (Sp. Pl.: 3. 1753) recognized two named varieties under Salicornia eu-
ropaea. Since S. europaea has no holotype and no syntypes are cited, both varietal names
are validly published irrespective of the facts that the lectotype of S. europaea, designated
by Jafri and Rateeb (in Jafri & El-Gadi, Fl. Libya 58: 57. 1979), can be attributed to S. eu-
ropaea var. herbacea L. (1753) and that the latter name was subsequently lectotypified by
Piirainen (in Ann. Bot. Fenn. 28: 82. 1991) by the same specimen as the species name.

Ex. 4.  Linnaeus (Sp. Pl.: 779-781. 1753) recognized 13 named varieties under Medicago
polymorpha. Since M. polymorpha L. has neither a holotype nor syntypes, all varietal
names are validly published, and indeed the lectotype subsequently designated (by Heyn in
Bull. Res. Council Israel, Sect. D, Bot., 7: 163. 1959) is not part of the original material for
any of the varietal names of 1753.

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26.3.  The first instance of valid publication of a name of an infraspecific
taxon under a legitimate species name automatically establishes the corre-
sponding autonym (see also Art. 32.6 and 11.6).

Ex. 5.  The publication of the name Lycopodium inundatum var. bigelovii Tuck. (in Amer.
J. Sci. Arts 45: 47. 1843) automatically established the name of another variety, L. inun-
datum L. var. inundatum, the type of which is that of the name L. inundatum L.

Ex. 6.  Utricularia stellaris L. f. (1782) includes U. stellaris var. coromandeliana A. DC.
(Prodr. 8: 3. 1844) and U. stellaris L. f. var. stellaris (1844) automatically established at
the same time. When U. stellaris is included in U. inflexa Forssk. (1775) as a variety, the
correct name of that variety, under Art. 11.6, is U. inflexa var. stellaris (L. f.) P. Taylor
(1961).

Ex. 7.  Pangalo (in Trudy Prikl. Bot. 23: 258. 1930) when describing Cucurbita mixta
Pangalo distinguished two varieties, C. mixta var. cyanoperizona Pangalo and var. steno-
sperma Pangalo, together encompassing the entire circumscription of the species. Since
neither a holotype nor any syntypes were indicated for C. mixta, both varietal names were
validly published (see Art. 26.2). Merrick & Bates (in Baileya 23: 96, 101. 1989), in the
absence of known type material, neotypified C. mixta by an element that can be attributed
to C. mixta var. stenosperma. As long as their choice of neotype is followed, the correct
name for that variety is C. mixta var. mixta, not C. mixta var. stenosperma. When it is
treated as a variety of C. argyrosperma Huber (1867), as by Merrick & Bates, its correct
name under Art. 11.6 is not C. argyrosperma var. stenosperma (Pangalo) Merrick & D. M.
Bates; a combination based on C. mixta is required.

Recommendation 26A

26A.1.  A variety including the type of the correct name of a subspecies, but not
including the type of the correct name of the species, should, where there is no
obstacle under the rules, be given a name with the same final epithet and type as
the subspecies name.

26A.2.  A subspecies not including the type of the correct name of the species
should, where there is no obstacle under the rules, be given a name with the same
final epithet and type as a name of one of its subordinate varieties.

26A.3.  A taxon of rank lower than variety which includes the type of the correct
name of a subspecies or variety, but not the type of the correct name of the spec-
ies, should, where there is no obstacle under the rules, be given a name with the
same final epithet and type as the name of the subspecies or variety. On the other
hand, a subspecies or variety which does not include the type of the correct name
of the species should not be given a name with the same final epithet as a name of
one of its subordinate taxa below the rank of variety.

Ex. 1.  Fernald treated Stachys palustris subsp. pilosa (Nutt.) Epling (in Repert. Spec. Nov.
Regni Veg. Beih. 8: 63. 1934) as composed of five varieties, for one of which (that in-
cluding the type of S. palustris subsp. pilosa) he made the combination S. palustris var.
pilosa (Nutt.) Fernald (in Rhodora 45: 474. 1943), there being no legitimate varietal name
available.

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Ex. 2.  There being no legitimate name available at the rank of subspecies, Bonaparte made
the combination Pteridium aquilinum subsp. caudatum (L.) Bonap. (Notes Ptérid. 1: 62.
1915), using the same final epithet that Sadebeck had used earlier in the combination
P. aquilinum var. caudatum (L.) Sadeb. (in Jahrb. Hamburg. Wiss. Anst. Beih. 14(3): 5.
1897), both combinations being based on Pteris caudata L. Each name is legitimate, and
both can be used, as by Tryon (in Rhodora 43: 52-54. 1941), who treated P. aquilinum var.
caudatum as one of four varieties under subsp. caudatum (see Art. 34.2).

Article 27

27.1.  The final epithet in the name of an infraspecific taxon may not re-
peat unchanged the epithet of the correct name of the species to which the
taxon is assigned unless the two names have the same type.

27.2.  The final epithet in the name of an infraspecific taxon may not re-
peat unchanged the epithet of the species name if that species name is
illegitimate.

SECTION 6. NAMES OF PLANTS IN CULTIVATION

Article 28

28.1.  Plants brought from the wild into cultivation retain the names that
are applied to the same taxa growing in nature.

Note 1.  Hybrids, including those arising in cultivation, may receive names as
provided in App. I (see also Art. 11.8, 40, and 50).

Note 2.  Additional, independent designations for special categories of plants used
in agriculture, forestry, and horticulture (and arising either in nature or cultiva-
tion) are dealt with in the International code of nomenclature for cultivated
plants, where the term “cultivar” is defined and regulations are provided for the
formation and use of cultivar epithets.

Note 3.  Nothing precludes the use, for cultivated plants, of names published in
accordance with the requirements of the botanical Code.

Note 4.  Epithets in names published in conformity with the botanical Code may
be used as cultivar epithets under the rules of the International code of nomen-
clature for cultivated plants, when cultivar is considered to be the appropriate
status for the groups concerned.

Ex. 1.  Mahonia japonica DC. (1821) may be treated as a cultivar, which is then desig-
nated as Mahonia ‘Japonica’; Taxus baccata var. variegata Weston (1770), when treated
as a cultivar, is designated as Taxus baccata ‘Variegata’.

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Note 5.  The International code of nomenclature for cultivated plants provides for
the establishment of cultivar epithets differing markedly from epithets in Latin
form.

Ex. 2.  ×Disophyllum ‘Frühlingsreigen’; Eriobotrya japonica ‘Golden Ziad’ and E. japonica
‘Maamora Golden Yellow’; Phlox drummondii ‘Sternenzauber’; Quercus frainetto ‘Hun-
garian Crown’

Ex. 3.  Juniperus ×pfitzeriana ‘Wilhelm Pfitzer’ (P. A. Schmidt 1998) was established for
a tetraploid cultivar presumed to result from the original cross between J. chinensis L. and
J. sabina L.

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CHAPTER IV. EFFECTIVE AND VALID PUBLICATION

SECTION 1. CONDITIONS AND DATES OF EFFECTIVE PUBLICATION

Article 29

29.1.  Publication is effected, under this Code, only by distribution of
printed matter (through sale, exchange, or gift) to the general public or at
least to botanical institutions with libraries accessible to botanists gener-
ally. It is not effected by communication of new names at a public meet-
ing, by the placing of names in collections or gardens open to the public,
by the issue of microfilm made from manuscripts, typescripts or other
unpublished material, by publication online, or by dissemination of dis-
tributable electronic media.

Ex. 1.  Cusson announced his establishment of the genus Physospermum in a memoir read
at the Société des Sciences de Montpellier in 1770, and later in 1782 or 1783 at the Société
de Médecine de Paris, but its effective publication dates from 1787 (in Hist. Soc. Roy.
Méd. 5(1): 279).

Article 30

30.1.  Publication by indelible autograph before 1 January 1953 is effec-
tive. Indelible autograph produced at a later date is not effectively pub-
lished.

Ex. 1.  Salvia oxyodon Webb & Heldr. was effectively published in an indelible autograph
catalogue placed on sale (Webb & Heldreich, Catalogus plantarum hispanicarum ... ab A.
Blanco lectarum, Paris, Jul 1850, folio).

Ex. 2.  The Journal of the International Conifer Preservation Society, vol. 5[1]. 1997
(“1998”), consists of duplicated sheets of typewritten text with handwritten additions and
corrections in several places. The handwritten portions, being indelible autograph pub-
lished after 1 January 1953, are not effectively published. Intended new combinations
(“Abies koreana var. yuanbaoshanensis”, p. 53) for which the basionym reference is
handwritten are not validly published. The entirely handwritten account of a new taxon
(p. 61: name, Latin description, statement of type) is treated as unpublished (see also Rec.
34A.1).

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30.2.  For the purpose of this Article, indelible autograph is handwritten
material reproduced by some mechanical or graphic process (such as li-
thography, offset, or metallic etching).

Ex.3.  Léveillé, Flore du Kouy Tchéou (1914-1915), is a work lithographed from a hand-
written text.

30.3.  Publication on or after 1 January 1953 in trade catalogues or non-
scientific newspapers, and on or after 1 January 1973 in seed-exchange
lists, does not constitute effective publication.

30.4.  The distribution on or after 1 January 1953 of printed matter ac-
companying exsiccata does not constitute effective publication.

Note 1.  If the printed matter is also distributed independently of the exsiccata, it
is effectively published.

Ex. 4.  The printed labels of Fuckel’s Fungi rhenani exsiccati (1863-1874) are effectively
published even though not independently issued. The labels antedate Fuckel’s subsequent
accounts (e.g., in Jahrb. Nassauischen Vereins Naturk. 23-24. 1870).

Ex. 5.  Vězda’s Lichenes selecti exsiccati (1967-) were issued with printed labels that were
also distributed independently as printed fascicles; the latter are effectively published and
new names appearing in Vězda’s exsiccata are to be cited from the fascicles.

Recommendation 30A

30A.1.  It is strongly recommended that authors avoid publishing new names and
descriptions or diagnoses of new taxa in ephemeral printed matter of any kind, in
particular printed matter that is multiplied in restricted and uncertain numbers, in
which the permanence of the text may be limited, for which effective publication
in terms of number of copies is not obvious, or that is unlikely to reach the gen-
eral public. Authors should also avoid publishing new names and descriptions or
diagnoses in popular periodicals, in abstracting journals, or on correction slips.

Ex. 1.  Kartesz provided an unpaged, printed insert titled “Nomenclatural innovations” to
accompany the electronic version (1.0) of the Synthesis of the North American flora pro-
duced on compact disk (CD-ROM; a distributable electronic medium in terms of Art
29.1). This insert, which is effectively published under Art. 29-30, is the place of valid
publication of 41 new combinations, which also appear on the disk, in an item authored by
Kartesz: “A synonymized checklist and atlas with biological attributes for the vascular
flora of the United States, Canada, and Greenland” (e.g., Dichanthelium hirstii (Swallen)
Kartesz in Kartesz & Meacham, Synth. N. Amer. Fl., Nomencl. Innov.: [1]. Aug 1999).
Kartesz’s procedure is not to be recommended, as the insert is unlikely to be permanently
stored and catalogued in botanical libraries and so reach the general public.

30A.2.  Authors publishing nomenclatural novelties should give preference to
periodicals that regularly publish taxonomic articles, or else they should send a
copy of their work to the appropriate indexing centre(s).

30A.3.  Authors and editors are encouraged to mention nomenclatural novelties in
the summary or abstract, or list them in an index in the publication.

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Article 31

31.1.  The date of effective publication is the date on which the printed
matter became available as defined in Art. 29 and 30. In the absence of
proof establishing some other date, the one appearing in the printed matter
must be accepted as correct.

Ex. 1.  Individual parts of Willdenow’s Species plantarum were published as follows: 1(1),
Jun 1797; 1(2), Jul 1798; 2(1), Mar 1799; 2(2), Dec 1799; 3(1), 1800; 3(2), Nov 1802;
3(3), Apr-Dec 1803; 4(1), 1805; 4(2), 1806; these dates are presently accepted as the dates
of effective publication (see Stafleu & Cowan in Regnum Veg. 116: 303. 1988).

Ex. 2.  T. M. Fries first published Lichenes arctoi in 1860 as an independently paginated
preprint, which predates the identical version published in a journal (Nova Acta Reg. Soc.
Sci. Upsal. ser. 3, 3: 103-398. 1861).

31.2.  When separates from periodicals or other works placed on sale are
issued in advance, the date on the separate is accepted as the date of ef-
fective publication unless there is evidence that it is erroneous.

Ex. 3.  The names of the Selaginella species published by Hieronymus (in Hedwigia 51:
241-272) were effectively published on 15 October 1911, since the volume in which the
paper appeared, though dated 1912, states (p. ii) that the separate appeared on that date.

Recommendation 31A

31A.1.  The date on which the publisher or publisher’s agent delivers printed
matter to one of the usual carriers for distribution to the public should be accepted
as its date of effective publication.

SECTION 2. CONDITIONS AND DATES OF VALID PUBLICATION OF

NAMES

Article 32

32.1.  In order to be validly published, a name of a taxon (autonyms ex-
cepted) must: (a) be effectively published (see Art. 29-31) on or after the
starting-point date of the respective group (Art. 13.1); (b) have a form
which complies with the provisions of Art. 16-27 (but see Art. 18.3, 19.5,
and 24.4), and Art. H.6 and H.7; (c) be accompanied by a description or
diagnosis or by a reference to a previously and effectively published de-
scription or diagnosis (except as provided in Art. 42.3, 44.1, and H.9); and
(d) comply with the special provisions of Art. 33-45 (see also Art. 61).

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Ex. 1.  “Egeria” (Néraud in Gaudichaud, Voy. Uranie, Bot.: 25, 28. 1826), published
without a description or a diagnosis or a reference to a former one, was not validly pub-
lished.

Ex. 2.  “Loranthus macrosolen Steud.” originally appeared without a description or diag-
nosis on the printed labels issued about the year 1843 with Sect. II, No. 529, 1288, of
Schimper’s herbarium specimens of Abyssinian plants; the name was not validly pub-
lished, however, until Richard (Tent. Fl. Abyss. 1: 340. 1847) supplied a description.

*Ex. 3.  In Don, Sweet’s Hortus britannicus, ed. 3 (1839), for each listed species the flower
colour, the duration of the plant, and a translation into English of the specific epithet are
given in tabular form. In many genera the flower colour and duration may be identical for all
species and clearly their mention is not intended as a validating description or diagnosis. New
names appearing in that work are therefore not validly published, except in some cases where
reference is made to earlier descriptions or diagnoses or to validly published basionyms.

32.2.  A diagnosis of a taxon is a statement of that which in the opinion of
its author distinguishes the taxon from others.

32.3.  For the purpose of valid publication of a name, reference to a previ-
ously and effectively published description or diagnosis may be direct or
indirect (Art. 32.4). For names published on or after 1 January 1953 it
must, however, be full and direct as specified in Art. 33.3.

32.4.  An indirect reference is a clear (if cryptic) indication, by an author
citation or in some other way, that a previously and effectively published
description or diagnosis applies.

Ex. 4.  “Kratzmannia” (Opiz in Berchtold & Opiz, Oekon.-Techn. Fl. Böhm. 1: 398. 1836)
was published with a diagnosis but was not definitely accepted by the author and therefore
was not validly published. Kratzmannia Opiz (Seznam: 56. 1852), lacking description or
diagnosis, is however definitely accepted, and its citation as “Kratzmannia O.” constitutes
indirect reference to the diagnosis published in 1836.

Ex. 5.  Opiz published the name of the genus Hemisphace (Benth.) Opiz (1852) without a
description or diagnosis, but as he wrote “Hemisphace Benth.” he indirectly referred to the
previously effectively published description by Bentham (Labiat. Gen. Spec.: 193. 1833)
of Salvia sect. Hemisphace.

Ex. 6.  The new combination Cymbopogon martini (Roxb.) W. Watson (1882) is validated
by the addition of the number “309”, which, as explained at the top of the same page, is the
running-number of the species (Andropogon martini Roxb.) in Steudel (Syn. Pl. Glumac.
1: 388. 1854). Although the reference to the basionym Andropogon martini is indirect, it is
unambiguous (but see Art. 45 Ex. 1; see also Rec. 60C.2).

Ex. 7.  Miller (1768), in the preface to The gardeners dictionary, ed. 8, stated that he had
“now applied Linnaeus’s method entirely except in such particulars ...”, of which he gave
examples. In the main text, he often referred to Linnaean genera under his own generic
headings, e.g., to Cactus L. [pro parte] under Opuntia Mill. Therefore an implicit reference to a
Linnaean binomial may be assumed when this is appropriate, and Miller’s binomials are then
accepted as new combinations (e.g., Opuntia ficus-indica (L.) Mill., based on Cactus ficus-
indica L.) or nomina nova (e.g., Opuntia vulgaris Mill., based on Cactus opuntia L.: both
names have the reference to “Opuntia vulgo herbariorum” of Bauhin & Cherler in common).

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Ex. 8.  In Kummer’s Führer in die Pilzkunde (1871) the statement that the author intended
to adopt at generic rank the subdivisions of Agaricus then in use, which at the time were
those of Fries, and the general arrangement of the work, which faithfully follows that of
Fries, provide indirect reference to Fries’s earlier names of “tribes”. Therefore, names such
as Hypholoma (Fr. : Fr.) P. Kumm. are accepted as being based on the corresponding
Friesian names (here: A. “tribus” Hypholoma Fr. : Fr.) although Kummer did not explicitly
refer to Fries.

32.5.  Names or epithets published with an incorrect Latin termination but
otherwise in accordance with this Code are regarded as validly published;
they are to be changed to accord with Art. 17-20, 21, 23, and 24, without
change of the author citation or date of publication (see also Art. 60.11).

32.6.  Autonyms (Art. 6.8) are accepted as validly published names, dat-
ing from the publication in which they were established (see Art. 22.3 and
26.3), whether or not they appear in print in that publication.

32.7.  Names in specified ranks included in publications listed as sup-
pressed works (opera utique oppressa; App. V) are not validly published.
Proposals for the addition of publications to App. V must be submitted to
the General Committee (see Div. III), which will refer them for examina-
tion to the committees for the various taxonomic groups (see Rec. 32F;
see also Art. 14.14 and Rec. 14A).

32.8.  When a proposal for the suppression of a publication as been ap-
proved by the General Committee after study by the committees for the
taxonomic groups concerned, suppression of that publication is authorized
subject to the decision of a later International Botanical Congress.

Note. 1.  For valid publication of names of plant taxa that were originally not
treated as plants, see Art. 45.4.

Recommendation 32A

32A.1.  A name should not be validated solely by a reference to a description or
diagnosis published before 1753.

Recommendation 32B

32B.1.  The description or diagnosis of any new taxon should mention the points
in which the taxon differs from its allies.

Recommendation 32C

32C.1.  When naming a new taxon, authors should not adopt a name that has been
previously but not validly published for a different taxon.

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Recommendation 32D

32D.1.  In describing or diagnosing new taxa, authors should, when possible,
supply figures with details of structure as an aid to identification.

32D.2.  In the explanation of the figures, authors should indicate the specimen(s)
on which they are based (see also Rec. 8A.2).

32D.3.  Authors should indicate clearly and precisely the scale of the figures
which they publish.

Recommendation 32E

32E.1.  Descriptions or diagnoses of parasitic plants should always be followed
by indication of the hosts, especially those of parasitic fungi. The hosts should be
designated by their scientific names and not solely by names in modern lan-
guages, the applications of which are often doubtful.

Recommendation 32F

32F.1.  When a proposal for the suppression of a publication under Art. 32.7 has
been referred to the appropriate committees for study, authors should follow
existing usage as far as possible pending the General Committee’s recommenda-
tion on the proposal.

Article 33

33.1.  A combination (autonyms excepted) is not validly published unless
the author definitely associates the final epithet with the name of the ge-
nus or species, or with its abbreviation.

Ex. 1.  Combinations validly published: In Linnaeus’s Species plantarum the placing of the
epithet in the margin opposite the name of the genus clearly associates the epithet with the
name of the genus. The same result is attained in Miller’s Gardeners dictionary, ed. 8, by
the inclusion of the epithet in parentheses immediately after the name of the genus, in
Steudel’s Nomenclator botanicus by the arrangement of the epithets in a list headed by the
name of the genus, and in general by any typographical device which associates an epithet
with a particular generic or specific name.

Ex. 2.  Combinations not validly published: Rafinesque’s statement under Blephilia that
“Le type de ce genre est la Monarda ciliata Linn.” (in J. Phys. Chim. Hist. Nat. Arts 89:
98. 1819) does not constitute valid publication of the combination B. ciliata, since Rafi-
nesque did not definitely associate the epithet ciliata with the generic name Blephilia.
Similarly, the combination Eulophus peucedanoides is not to be attributed to Bentham &
Hooker (Gen. Pl. 1: 885. 1867) on the basis of their listing of “Cnidium peucedanoides,
H. B. et K.” under Eulophus.

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33.2.  If, for a presumed new combination, no reference to a basionym is
given but the epithet of a previously and validly published name that ap-
plies to the same taxon is adopted, the new combination is validly pub-
lished as such if, and only if, it would otherwise be validly published as
the name of a new taxon (see also Art. 33.6(d)).

Ex. 3.  Scaevola taccada was validly published by Roxburgh (1814) by reference to an
illustration in Rheede (Hort. Malab. 4: t. 59. 1683) that appears to be its sole basis. As the
name applies to the species previously described as Lobelia taccada Gaertn. (1788), it is
treated as a new combination, S. taccada (Gaertn.) Roxb., not as the name of a new spe-
cies, even though Gaertner is not referred to in Roxburgh’s protologue.

33.3.  A new combination, or an avowed substitute (replacement name,
nomen novum), published on or after 1 January 1953 based on a previ-
ously and validly published name is not validly published unless its ba-
sionym (name-bringing or epithet-bringing synonym) or the replaced
synonym (when a new name is proposed) is clearly indicated and a full
and direct reference given to its author and place of valid publication, with
page or plate reference and date (but see Art. 33.2, 33.4, and 33.6).

Ex. 4.  In transferring Ectocarpus mucronatus D. A. Saunders to Giffordia, Kjeldsen &
Phinney (in Madroño 22: 90. 27 Apr 1973) cited the basionym and its author but without
reference to its place of valid publication. They later (in Madroño 22: 154. 2 Jul 1973)
validated the binomial G. mucronata (D. A. Saunders) Kjeldsen & Phinney by giving a full
and direct reference to the place of valid publication of the basionym.

Note 1.  For the purpose of this Code, a page reference (for publications with a
consecutive pagination) is a reference to the page or pages on which the ba-
sionym was validly published or on which the protologue is printed, but not to the
pagination of the whole publication unless it is coextensive with that of the pro-
tologue.

Ex. 5.  When proposing “Cylindrocladium infestans”, Peerally (in Mycotaxon 40: 337.
1991) cited the basionym as “Cylindrocladiella infestans Boesw., Can. J. Bot. 60: 2288-
2294. 1982”. As this refers to the pagination of Boeswinkel’s entire paper, not of the pro-
tologue of the intended basionym alone, the combination was not validly published by
Peerally.

33.4.  Errors in the citation of the basionym or replaced synonym, including
incorrect author citation (Art. 46), but not omissions (Art. 33.3; but
see Art. 33.2), do not invalidate publication of a new combination or no-
men novum.

Ex. 6.  Aronia arbutifolia var. nigra (Willd.) F. Seym. (Fl. New England: 308. 1969) was
published as a new combination “Based on Mespilus arbutifolia L. var. nigra Willd., in Sp.
Pl. 2: 1013. 1800.” Willdenow treated these plants in the genus Pyrus, not Mespilus, and
publication was in 1799, not 1800; these errors are treated as bibliographic errors of cita-
tion and do not invalidate the publication of the new combination.

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33.5.  Mere reference to the Index kewensis, the Index of fungi, or any
work other than that in which the name was validly published does not
constitute a full and direct reference to the original publication of a name
(but see Art. 33.6) .

Ex. 7.  Ciferri (in Mycopathol. Mycol. Appl. 7: 86-89. 1954), in proposing 142 new com-
binations in Meliola, omitted references to places of publication of basionyms, stating that
they could be found in Petrak’s lists or in the Index of fungi; none of these combinations
was validly published. Similarly, Grummann (Cat. Lich. Germ.: 18. 1963) introduced a new
combination in the form Lecanora campestris f. “pseudistera (Nyl.) Grumm. c.n. – L. p.
Nyl., Z 5: 521”, in which “Z 5” referred to Zahlbruckner (Cat. Lich. Univ. 5: 521. 1928),
who gave the full citation of the basionym, Lecanora pseudistera Nyl.; Grummann’s com-
bination was not validly published.

Note 2.  The publication of a name for a taxon previously known under a misap-
plied name must be valid under Art. 32-45. This procedure is not the same as
publishing an avowed substitute (replacement name, nomen novum) for a validly
published but illegitimate name (Art. 58.1), the type of which is necessarily the
same as that of the name which it replaced (Art. 7.3).

Ex. 8.  Sadleria hillebrandii Rob. (1913) was introduced as a “nom. nov.” for “Sadleria
pallida Hilleb. Fl. Haw. Is. 582. 1888. Not Hook. & Arn. Bot. Beech. 75. 1832.” Since the
requirements of Art. 32-45 were satisfied (for valid publication, prior to 1935, simple
reference to a previous description or diagnosis in any language was sufficient), the name
is validly published. It is, however, to be considered the name of a new species, validated
by Hillebrand’s description of the taxon to which he misapplied the name S. pallida Hook.
& Arn., and not a nomen novum as stated by Robinson; hence, Art. 7.3 does not apply.

Ex. 9.  Juncus bufonius “var. occidentalis” (Hermann in U.S. Forest Serv., Techn. Rep.
RM-18: 14. 1975) was published as a “nom. et stat. nov.” for J. sphaerocarpus “auct. Am.,
non Nees”. Since there is no Latin diagnosis, designation of type, or reference to any pre-
vious publication providing these requirements, the name is not validly published.

33.6.  In any of the following cases, reference to a work other than that in
which the basionym or replaced synonym was validly published is treated
as an error to be corrected, not affecting the valid publication of a new
combination or nomen novum, even if published on or after 1 January
1953:

(a)  when the name cited as basionym or replaced synonym was validly
      published earlier than in the cited publication, but in that cited publi-
      cation, in which all conditions for valid publication are again fulfilled,
      there is no reference to the actual place of valid publication;

(b)  when the failure to cite the place of valid publication of the basionym
      or replaced synonym is explained by the later nomenclatural starting
      point for the group concerned, and in particular by the backward shift
      of the starting date for some fungi;

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(c)  when an intended new combination would otherwise be validly pub-
      lished as a (legitimate or illegitimate) nomen novum; or

(d)  when an intended new combination or nomen novum would otherwise
      be the validly published name of a new taxon (see also Art. 33.2).

Ex. 10.  The combination Trichipteris kalbreyeri was proposed by Tryon (1970) with a full
and direct reference to “Alsophila Kalbreyeri C. Chr. Ind. Fil. 44. 1905”. This, however, is
not the place of valid publication of the intended basionym, which had previously been
published, with the same type, by Baker (1891; see Art. 6 Ex. 1). As Christensen provided
no reference to Baker’s earlier validation, Tryon’s error of citation does not affect the valid
publication of his new combination, which is to be cited as T. kalbreyeri (Baker) R. M.
Tryon.

Ex. 11.  The intended new combination “Machaerina iridifolia” was proposed by Koyama
(in Bot. Mag. (Tokyo) 69: 64. 1956) with a full and direct reference to “Cladium iridifo-
lium Baker, Flor. Maurit. 424 (1877)”. However, C. iridifolium had been proposed by
Baker as a new combination based on Scirpus iridifolius Bory (1804). As Baker provided
an explicit reference to Bory, Art. 33.6(a) does not apply and the combination under Ma-
chaerina was not validly published by Koyama.

Ex. 12.  The combination Lasiobelonium corticale was proposed by Raitviir (1980) with a
full and direct reference to Peziza corticalis in Fries (Syst. Mycol. 2: 96. 1822). This,
however, is not the place of valid publication of the basionym, which, under the Code
operating in 1980, was in Mérat (Nouv. Fl. Env. Paris, ed. 2, 1: 22. 1821), and under the
current Code is in Persoon (Observ. Mycol. 1: 28. 1796). Raitviir’s error of citation, being
partly explained by the backward shift of the starting date for ascomycetes and partly by
the absence of a reference to Mérat in Fries’s work, does not invalidate the publication of
the new combination, which is to be cited as L. corticale (Pers. : Fr.) Raitv.

33.7.  A name given to a taxon of which the rank is at the same time, con-
trary to Art. 5, denoted by a misplaced term is not validly published. Such
misplacements include forms divided into varieties, species containing
genera, and genera containing families or tribes.

Ex. 13.  “Sectio Orontiaceae” was not validly published by Brown (Prodr.: 337. 1810)
since he misapplied the term “sectio” to a rank higher than genus.

Ex. 14.  “Tribus Involuta” and “tribus Brevipedunculata” (Huth in Bot. Jahrb. Syst. 20:
365, 368. 1895) are not validly published names, since Huth misapplied the term “tribus”
to a rank lower than section, within the genus Delphinium.

33.8.  An exception to Art. 33.7 is made for names of the subdivisions of
genera termed tribes (tribus) in Fries’s Systema mycologicum, which are
treated as validly published names of subdivisions of genera.

Ex. 15.  Agaricus “tribus” Pholiota Fr. (Syst. Mycol. 1: 240. 1821), sanctioned in the same
work, is the validly published basionym of the generic name Pholiota (Fr. : Fr.) P. Kumm.
(1871) (see Art. 32 Ex. 8).

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Recommendation 33A

33A.1.  The full and direct reference to the place of publication of the basionym
or replaced synonym should immediately follow a proposed new combination or
nomen novum. It should not be provided by mere cross-reference to a bibliogra-
phy at the end of the publication or to other parts of the same publication, e.g. by
use of the abbreviations “loc. cit.” or “op. cit.”

Article 34

34.1.  A name is not validly published (a) when it is not accepted by the
author in the original publication; (b) when it is merely proposed in anti-
cipation of the future acceptance of the group concerned, or of a particular
circumscription, position, or rank of the group (so-called provisional
name), except as provided for in Art. 59; (c) when it is merely cited as a
synonym; (d) by the mere mention of the subordinate taxa included in the
taxon concerned. Art. 34.1(a) does not apply to names published with a
question mark or other indication of taxonomic doubt, yet accepted by
their author.

Ex. 1.  (a) “Sebertia”, proposed by Pierre (ms.) for a monotypic genus, was not validly
published by Baillon (in Bull. Mens. Soc. Linn. Paris 2: 945. 1891) because he did not
accept the genus. Although he gave a description of it, he referred its only species “Seber-
tia acuminata Pierre (ms.)” to the genus Sersalisia R. Br. as S. ? acuminata, which he
thereby validly published under the provision of Art. 34.1, last sentence. The name Seber-
tia was validly published by Engler (1897).

Ex. 2.  (a) The designations listed in the lefthand column of the Linnaean thesis Herbarium
amboinense defended by Stickman (1754) were not names accepted by Linnaeus upon
publication and are not validly published.

Ex. 3.  (a) (b) The designation “Conophyton”, suggested by Haworth (Rev. Pl. Succ.: 82.
1821) for Mesembryanthemum sect. Minima Haw. (Rev. Pl. Succ.: 81. 1821) in the words
“If this section proves to be a genus, the name of Conophyton would be apt”, was not a
validly published generic name since Haworth did not adopt it or accept the genus. The
name was validly published as Conophytum N. E. Br. (1922).

Ex. 4.  (b) “Pteridospermaexylon” and “P. theresiae” were published by Greguss (in
Földt. Közl. 82: 171. 1952) for a genus and species of fossil wood. As Greguss explicitly
stated “Vorläufig benenne ich es mit den Namen ...” [provisionally I designate it by the
names ...], these are provisional names and as such are not validly published.

Ex. 5.  (c) “ Acosmus Desv.” was not validly published by Desfontaines (Cat. Pl. Hort.
Paris.: 233. 1829) when he cited it as a synonym of the generic name Aspicarpa Rich.

Ex. 6.  (c) “ Ornithogalum undulatum hort. Bouch.” was not validly published by Kunth,
(Enum. Pl. 4: 348. 1843) when he cited it as a synonym under Myogalum boucheanum
Kunth; the combination under Ornithogalum L. was validly published later: O. bouche-
anum (Kunth) Asch. (1866).

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Ex. 7.  (d) The family designation “Rhaptopetalaceae” was not validly published by Pierre
(in Bull. Mens. Soc. Linn. Paris 2: 1296. Mai 1897), who merely mentioned the constituent
genera, Brazzeia Baill., “Scytopetalum”, and Rhaptopetalum Oliv., but gave no descrip-
tion or diagnosis; the family bears the name Scytopetalaceae Engl. (Oct 1897), accompa-
nied by a description.

Ex. 8.  (d) The generic designation “Ibidium” was not validly published by Salisbury (in
Trans. Hort. Soc. London 1: 291. 1812) who merely mentioned four included species but
supplied no generic description or diagnosis.

34.2.  When, on or after 1 January 1953, two or more different names
based on the same type are proposed simultaneously for the same taxon by
the same author (so-called alternative names), none of them is validly
published. This rule does not apply in those cases where the same combi-
nation is simultaneously used at different ranks, either for infraspecific
taxa within a species or for subdivisions of a genus within a genus (see
Rec. 22A.1 and 22A.2, 26A.1-3).

Ex. 9.  The species of Brosimum Sw. described by Ducke (in Arch. Jard. Bot. Rio de Ja-
neiro 3: 23-29. 1922) were published with alternative names under Piratinera Aubl. added
in a footnote (pp. 23-24). The publication of both sets of names, being effected before
1 January 1953, is valid.

Ex. 10.  “Euphorbia jaroslavii” (Poljakov in Bot. Mater. Gerb. Bot. Inst. Komarova Akad.
Nauk SSSR 15: 155. 1953) was published with an alternative designation, “Tithymalus ja-
roslavii”. Neither was validly published. However, one name, Euphorbia yaroslavii (with
a different transliteration of the initial letter), was validly published by Poljakov (1961),
who effectively published it with a new reference to the earlier publication and simultane-
ously rejected the other name.

Ex. 11.  Description of “Malvastrum bicuspidatum subsp. tumidum S. R. Hill var. tumi-
dum, subsp. et var. nov.” (in Brittonia 32: 474. 1980) simultaneously validated both M. bi-
cuspidatum subsp. tumidum S. R. Hill and M. bicuspidatum var. tumidum S. R. Hill.

Ex. 12.  Hitchcock (in Univ. Wash. Publ. Biol. 17(1): 507-508. 1969) used the name Bro-
mus inermis subsp. pumpellianus (Scribn.) Wagnon and provided a full and direct reference
to its basionym, B. pumpellianus Scribn. Within that subspecies, he recognized varieties,
one of which he named B. inermis var. pumpellianus (without author citation but clearly
based on the same basionym and type). In so doing, he met the requirements for valid
publication of B. inermis var. pumpellianus (Scribn.) C. L. Hitchc.

Note 1.  The name of a fungal holomorph and that of a correlated anamorph (see
Art. 59), even if validated simultaneously, are not alternative names in the sense
of Art. 34.2. They have different types, and the circumscription of the holomorph
is considered to include the anamorph, but not vice versa.

Ex. 13.  Lasiosphaeria elinorae Linder (1929), the name of a fungal holomorph, and the
simultaneously published name of a correlated anamorph, Helicosporium elinorae Linder,
are both valid, and both can be used under Art. 59.5 (see also Rec. 60C.2).

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Recommendation 34A

34A.1.  Authors should avoid mentioning in their publications previously unpub-
lished names which they do not accept, especially if the persons responsible for these
unpublished names have not formally authorized their publication (see Rec. 23A.3(i)).

Article 35

35.1.  A new name or combination published on or after 1 January 1953
without a clear indication of the rank of the taxon concerned is not validly
published.

35.2.  For suprageneric names published on or after 1 January 1908, the
use of one of the terminations specified in Rec. 16A.1-3, Art. 17.1, 18.1,
19.1, and 19.3 is accepted as an indication of the corresponding rank, un-
less this (a) would conflict with the explicitly designated rank of the taxon
(which takes precedence) or (b) would result in a rank sequence contrary
to Art. 5 (in which case Art. 33.7 applies).

Ex. 1.  Jussieu (in Mém. Mus. Hist. Nat. 12: 497. 1827) proposed Zanthoxyleae without
specifying the rank. Although he employed the present termination for tribe (-eae), that
name, being published prior to 1908, is unranked. Zanthoxyleae Dumort. (Anal. Fam. Pl.:
45. 1829), however, is a tribal name, as Dumortier specified its rank.

Ex. 2.  Nakai (Chosakuronbun Mokuroku [Ord. Fam. Trib. Nov.], 1943) validly published
the names Parnassiales, Lophiolaceae, Ranzanioideae, and Urospatheae. He indicated the
respective ranks of order, family, subfamily, and tribe, by virtue of their terminations, even
though he did not mention these ranks explicitly.

35.3.  A new name or combination published before 1 January 1953 with-
out a clear indication of its rank is validly published provided that all
other requirements for valid publication are fulfilled; it is, however, inop-
erative in questions of priority except for homonymy (see Art. 53.4). If it
is a new name, it may serve as a basionym for subsequent combinations or
a replaced synonym for nomina nova in definite ranks.

Ex. 3.  The groups “Soldanellae”, “Sepincoli”, “Occidentales”, etc., were published with-
out any indication of rank under Convolvulus L. by House (in Muhlenbergia 4: 50. 1908).
The names C. [unranked] Soldanellae, etc., are validly published but they are not in any defi-
nite rank and have no status in questions of priority except that they may act as homonyms.

Ex. 4.  In Carex L., the epithet Scirpinae was used in the name of an infrageneric taxon of
no stated rank by Tuckerman (Enum. Meth. Caric.: 8. 1843); this taxon was assigned
sectional rank by Kükenthal (in Engler, Pflanzenr. 38: 81. 1909) and its name may be cited
as Carex sect. Scirpinae (Tuck.) Kük. (C. [unranked] Scirpinae Tuck.).

35.4.  If in one whole publication (Art. 35.5), prior to 1 January 1890, only
one infraspecific rank is admitted, it is considered to be that of variety un-
less this would be contrary to the author’s statements in the same publication.

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35.5.  In questions of indication of rank, all publications appearing under
the same title and by the same author, such as different parts of a flora
issued at different times (but not different editions of the same work),
must be considered as a whole, and any statement made therein designat-
ing the rank of taxa included in the work must be considered as if it had
been published together with the first instalment.

Article 36

36.1.  On or after 1 January 1935 a name of a new taxon (algal and all
fossil taxa excepted) must, in order to be validly published, be accompa-
nied by a Latin description or diagnosis or by a reference to a previously
and effectively published Latin description or diagnosis (but see Art. H.9).

Ex. 1.  Arabis “Sekt. Brassicoturritis O. E. Schulz” and “Sekt. Brassicarabis O. E. Schulz”
(in Engler & Prantl, Nat. Pflanzenfam., ed. 2, 17b: 543-544. 1936), published with German
but no Latin descriptions or diagnoses, are not validly published names.

Ex. 2.  “Schiedea gregoriana” (Degener, Fl. Hawaiiensis, fam. 119. 9 Apr 1936) was ac-
companied by an English but no Latin description and is accordingly not a validly pub-
lished name. S. kealiae Caum & Hosaka (in Occas. Pap. Bernice Pauahi Bishop Mus.
11(23): 3. 10 Apr 1936), the type of which is part of the material used by Degener, is
provided with a Latin description and is validly published.