[CPN] Proposal to amend Article 21

[David Marjanovic]

This is largely reposted from Oct. 6th and March 29th, but incorporates 
Phil's proposals from Jan. 16th. I have also added more explanations (in 
brackets) and updated the names of the rank-based codes.

The entire text of what the amended Art. 21 would look like follows. 
There would be just Art. 21.1, Note 21.1.1, and Rec. 21A through C, of 
which 21A and 21B have examples.

==============================

21.1 [includes the remains of current Art. 21.3]. This code does not 
govern the establishment or precedence of the names of species or of 
categories[*] smaller than species. To be considered available (ICZN) or 
validly published (ICN, ICNP), a specific or infraspecific name must 
satisfy the provisions of the appropriate rank-based code (e.g., ICNP, 
ICN, ICZN), whether it is a new name or a replacement name (e.g., ICNP: 
deliberate substitute name, ICN: avowed substitute name, ICZN: new 
replacement name). This article contains recommendations on how to avoid 
confusion when publishing, or using previously published, specific or 
infraspecific names governed by rank-based codes in conjunction with 
clade names governed by this code.

[* This is really pedantic... I want to make clear that assigning a rank 
to a name doesn't automatically take that name out of the purview of the 
PhyloCode. Alain Dubois distinguishes "rank" and "category", "category" 
being for instance the kind of taxon described by a particular species 
concept.]

[current Note 21.1.1 deleted]

Note 21.1.1. In any particular classification, a species or 
infraspecific taxon may be identical in content to a clade, and a clade 
may be assigned the rank of species or that of an infraspecific 
category. In such cases, intercode synonymy may occur between this code 
and a rank-based one, because names governed by this code have a 
different form from specific or infraspecific names governed by the 
ICNP, ICN or ICZN. However, such redundancy is likely to be limited: 
assigning a rank to a clade name is not a nomenclatural act under this 
code, and the rank-based codes do not recognize the adoption of any 
species concept as a nomenclatural act -- under most species concepts, 
species need not be clades. This situation is similar to monospecific 
genera under the rank-based codes (cases where a genus and its type 
species are identical in content in a particular classification).

Rec. 21A [currently Art. 21.2, Art. 21.4 and Rec. 21.4B]. Under the 
rank-based codes (except the ICVCN), the name of every species or 
smaller category consists of two or more words, the first of which is 
the name of the genus to which the taxon in question is considered to 
belong at the moment. To satisfy this
requirement, a name implicitly or explicitly associated with the rank of 
genus must be used when establishing a new or replacement name for a 
species or smaller category. For names governed by the ICZN, this 
practice must be followed throughout the publication that establishes 
the name (ICZN article 11.4 
http://www.nhm.ac.uk/hosted-sites/iczn/code/includes/page.jsp?article=11&nfv=#4 
). When choosing such a generic name as part of a new or replacement 
name for a species or infraspecific taxon, authors should consider the 
nomenclatural consequences under both the appropriate rank-based code 
and this code. In general, a generic name[*] that is also an established 
clade name (Example 1), or is simultaneously being established as a 
clade name (Examples 2, 3), should be selected if possible. Otherwise, 
an existing generic name[*] may be used, even if the monophyly of the 
taxon associated with it is unknown or doubtful (Examples 3, 4). If the 
taxon to be named cannot be assigned to any taxon with which a generic 
name[*] has been associated under the appropriate rank-based code, the 
only option is to publish a new name to serve as a generic name under 
that code (Examples 4, 5, 6). This name may be simultaneously 
established as a clade name under this code (Example 5).

[* Rec. 21.4B currently says "a generic name (ICNB, ICBN) or genus-group 
name (ICZN)". This is wrong. Under the ICZN, the name of a species must 
contain the name of a genus; it is not allowed to use the name of a 
subgenus instead -- a subgeneric name may only be used in addition. Of 
course, it is allowed to promote a subgenus to genus rank, but this is a 
nomenclatural act separate from the naming of a new species.]

[no changes to the Examples, except that Example 4 contains an instance 
of *Hypotheticus* that is not italicized]

[current Art. 21.2 and 21.3 deleted except as noted above]

Rec. 21B [currently Rec. 21.4A and Rec. 21.5A]. When establishing a new 
or replacement name for a species, subspecies or variety under the 
appropriate rank-based code, some mechanism should be used to indicate 
whether the generic name is an established clade name under this code. 
If symbols are used, their meaning should be made clear.

[no changes to the Examples, except to replace "prenomen" with "generic 
name" throughout]

Rec. 21C [replaces current Rec. 21.4C]. When establishing a new species 
name under the appropriate rank-based code, the protologue should state 
which species concept the authors have in mind, and it should include a 
description of the evidence indicating that the new species fulfills 
that concept, even though the rank-based codes have no such requirements 
or recommendations. Names for infraspecific taxa should be handled 
analogously.

[current Art. 21.5 and Rec. 21A deleted; they are pretty much identical 
and should be merged into a Recommendation if kept; Art. 21.5 implies 
that there is such a thing as a species name under the PhyloCode, which 
there isn't]