[Taxacom] species inquirenda or nomen dubium

[dipteryx at freeler.nl]

As there is such a beautiful unanimity ("species inquirenda" is a term
that is used in a taxonomic context and "nomen dubium" is a term
that is used from a nomenclatural context) this will be my last post,
as there is no point in much repetition.

As they live in different worlds there is no possible confusion between 
these two terms, but maybe it will helpful to think of these as two sides 
of the same coin, sort of. This is not really a good analogy, as (unless 
things are very different in zoology than in botany) a species inquirenda 
does not necessarily have a name, nor is a nomen dubium necessarily
a name of a species. But in some cases it will come close enough to be 
useful.

BTW. I do not see why a catalogue may not be made from a taxonomic 
perspective. I would say that Wikispecies can be described as a catalogue
built from a particular taxonomic perspective. For a Checklist to be 
meaningful it is a requirement that it be made from a taxonomic perspective.

Paul

Van: taxacom-bounces at mailman.nhm.ku.edu namens Stephen Thorpe
Verzonden: ma 13-6-2011 1:14

yes, I was wondering how long it would take for someone to throw 'incertae 
sedis' (Dan Bickel's favourite group!) into the discussion ...

the only thing that does seem entirely clear is that these terms aren't entirely 
clear, and there is significant variation in understanding and usage

actually, I understand 'incertae sedis' to mean something quite different (I 
think!) to the others. A species incertae sedis would be, as always, referred to 
by a name (binomial), and I would say that there is *no doubt* that the name 
applies to that species, but that it cannot be decided to which genus the 
species should be assigned. This is very much a taxonomic/systematics problem.

as for the other two terms, my way of understanding them seems to have reached 
this:

a species inquirendum is a name (yes, a name!) of uncertain application. It is 
problematic to work out which species it applies to (for some reason, such 
as insufficient diagnostic characters in the type specimen, and/or 
description). But it is utterly hopeless to try to work out what species a nomen 
dubium applies to. If we want to use a name which is a nomen dubium for a 
species, then we *must* designate a neotype, and then the name isn't a nomen 
dubium any more. So, a nomen dubium is just the extreme case of a species 
inquirenda ... maybe ...

 

________________________________
From: Geoff Read <gread at actrix.gen.nz>
To: taxacom at mailman.nhm.ku.edu
Sent: Mon, 13 June, 2011 10:12:21 AM
Subject: Re: [Taxacom] species inquirenda or nomen dubium = BOTH!

There is a third label. What about 'incertae sedis' (lit. undetermined
seat, &  also defined by ICZN glossary)?  Is this more to be used for
uncertain placement in a hierarchy (genus or family unknown)?
A species inquirenda might also be incertae sedis, but a monograph known
to me confidently assigns a list of binomials to either species inquirenda
or incertae sedis. Not sure how/why, but possibly it's just repeating the
(arbitrary) terminology used by the prior authors.
Incertae sedis is seemingly a more frequently used term than species
inquirenda (ngrams.googlelabs.com).


Geoff

>>> On 13/06/2011 at 2:02 a.m., "Chris Thompson" <xelaalex at cox.net> wrote:
> Stephen:
>
> You are right to bring up this question.
>
> Most people confuse these terms or do not realize that it is the context
> that is critical.
>
> Species inquirenda is an taxonomical term and should only be used in the
> context of a taxonomy / systematic study (monograph, revision, etc.).
> And as others have pointed out this means a questionable species. That is,
> for some taxonomic reason, the species concept is not clearly defined. 
> That may be due to the lack of diagnostic characters or questions about
> biological parameters, like whether the individuals are inter-breeding 
> or not.
>
> nomen dubium (nomina dubia) is a nomenclatural term and is, as Paul noted,
> defined by the International Code of Zoological Nomenclature.