[Taxacom] Describing genera without molecular phyolgies

[Lynn Raw]

While a genus is purely an arbitrary concept, I like Mayr’s 1969, p.92-3, definition which is essentially that a genus is a single species or monophyletic group which is separated from other taxa by a decided (morphological) gap which is in inverse ration to the size of the taxon. Since taxonomic classification is essentially an information retrieval system, to be useful generally, I think that it is important that the gap should be defined by morphology rather than purely molecular evidence. If molecular evidence is available then both should be given and if the evidence does not agree then this should be explained. 

The simple absence of molecular evidence should never be an acceptable reason for rejection of a taxonomic paper.

Lynn Raw

Managing Editor ZooNova
http://zoonova.afriherp.org


> On 23 May 2020, at 17.55, John Grehan via Taxacom <taxacom at mailman.nhm.ku.edu> wrote:
> 
> I do agree that a phylogenetic relationship is critical, ideally with a
> complete (inclusive of all taxa in the group) analysis involving a thorough
> morphological and/or molecular analysis. Short of that I am faced in my
> group of interest (ghost moths) to at least define new genera as having one
> or more unique features - i.e. I cannot fit them within any current genera.
> When a molecular approach for the group as a whole (at family level) does
> appear in the future, the situation may not be improved substantially as I
> will assume that the initial molecular studies will be partial in scope,
> and then there remains that dreaded impasse between morphological  and
> molecular relationships that are in-congruent - if that happens. I've
> hopefully a few good years left and perhaps will be on hand to see what
> happens. Of course generic designations, apart from monophyly requirements,
> are entirely arbitrary. I have seen where molecular systematists have used
> a chosen level of molecular divergence to designate genera, which is fine
> if one likes to do that. For me the designation of different genera refer
> to some distincti
> 
> John Grehan
>