Later Homonyms

[John McNeill]

Solely on the basis of the information provided by Luciano Paganucci de Queiroz,
the correct name would be _Dioclea violacea_ Bentham (1837).

The relevant Articles are 11.4 and 58.1:

"11.4. For any taxon below the rank of genus, the correct name is the
combination of the final epithet 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, ....."

"58.1. A name rejected or otherwise unavailable for use under Art. 51, 52, 53,
54, or 56, 57, 58 is replaced by the name that has priority (Art. 11) in the
rank concerned. If none exists in any rank a new name must be chosen: ...."

As _Dolichos altissimus_ is illegitimate, it cannot provide the epithet for the
correct name and, from the info provided, no other legitimate name existed for
the species when Bentham named _Dioclea violacea_.

The status of _Dioclea altissima_ Rock (1920) is not clear from the information
provided.  If Rock cited _Dioclea violacea_ Benth. as a synonym, his name would
be illegitimate, but if he did not, and, for example, only cited the supposed
basionym _Dolichos altissimus_  Vellozo, the provisions of Art. 58.3 (see
below) would be applicable and _Dioclea altissima_ Rock would be a legitimate
new name (NOT a new combination, so no basionym author is cited);  as it would
only date to 1920, however, Bentham's name would have precedence.

"58.3. When a new epithet is required, an author may adopt the epithet
of a previous illegitimate name of the taxon if there is no obstacle to
its employment in the new position or sense; the resultant combination
is treated as the name of a new taxon or as a nomen novum, as the case
may be."

Hope this helps; let me know if I have overlooked something.

John McNeill

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      John McNeill, Director Emeritus, Royal Ontario Museum,
      100 Queen's Park, Toronto, Ontario, M5S 2C6, Canada.
      Telephone and fax number:  416-586-5744
      e-mail: johnm at rom.on.ca
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______________________________ Reply Separator _________________________________
Subject: Later Homonyms
Author:  LUCIANO PAGANUCCI DE QUEIROZ <lqueiroz at CASCAVEL.UEFS.BR> at Internet
Date:    12/03/99 3:46 PM


Dear Taxacomers,

        I looking for advice for a nomenclatural question: could later homonyms
be
used as a basionym for a not occupied name ? I have a problem like this:

        There are two competing names for a Dioclea species: Dioclea violacea an
d
Dioclea altissima.

- Dioclea violacea was published by Bentham in 1837

- Dioclea altissima is a combination proposed by Rock in 1920 based on
Dolichos altissimus publised by Vellozo in 1825.

- Dolichos altissimus Vellozo is a later homonym of Dolichos altissimus
Jacquin 1760, the basionym of Mucuna altissima (Jacq.) DC., 1825.

        It is obvious that Dolichos altissimus Vellozo is an illegitimate name a
nd
must be rejected, but it predates Dioclea violacea Bentham and the
combination Dioclea altissima is not occupied unless the Rock proposition.
I did not find an answer to this question at the chapter 5 of Botanical
Code. Do you have an opinion about the correct name for this taxon ?

LUCIANO




**********************
LUCIANO PAGANUCCI DE QUEIROZ
Universidade Estadual de Feira de Santana
Departamento de Ci=EAncias Biol=F3gicas
Herb=E1rio
Km 03 - BR 116, Campus
44031-460, Feira de Santana, Bahia, Brasil
Fone (075) 2248021
Fax (075) 2248019
E-mail: lqueiroz at uefs.br