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RE: Arcovenator, new abelisaurid theropod from Late Cretaceous of southern France



The phylogeny produced by Ezcurra et al. places *Abelisaurus comahuensis* in a 
polytomy with *Carnotaurus sastrei*, *Aucasaurus garridoi*, and a few other 
taxa. *Abelisaurus comahuensis* is closer to *Carnotaurus sastrei* than 
*Majungasaurus crenatissimus*, in conflict with past analyses in which Abeli 
was always outside of a Majunga+Carno clade (which was named *Carnotaurinae*). 
It is this analysis that moves Abeli inside *Carnotaurinae*, and within 
*Brachyrostra* and *Carnotaurini*. 

Ordinarily, we'd reassert *Abelisaurinae*, which has already been named, and it 
behooves the authors to consider this option when they went about coining 
names. But this wouldn't have affected *Majungasaurinae,* as the name as used 
is consistent with either position of Abeli. Problematically the 
*Carnotaurini*, *Majungasaurinae*, non-*Carnotaurinae* *Abelisauridae*, and 
"*Noasauridae*" nodes are not well-resolved, producing huge polytomies, and it 
is likely this will cause some of these taxa issues. Inclusion of further 
characters and taxa will change this up. Sadly, the support values of the 
phylogeny for these positions is not robust, so this topology is likely to 
change.

Cheers,

  Jaime A. Headden
  The Bite Stuff (site v2)
  http://qilong.wordpress.com/

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)


"Ever since man first left his cave and met a stranger with a
different language and a new way of looking at things, the human race
has had a dream: to kill him, so we don't have to learn his language or
his new way of looking at things." --- Zapp Brannigan (Beast With a Billion 
Backs)


----------------------------------------
> Date: Fri, 13 Dec 2013 21:16:52 +0100
> From: j.falconnet@gmail.com
> To: dinosaur@usc.edu
> Subject: Re: Arcovenator, new abelisaurid theropod from Late Cretaceous of 
> southern France
>
> First of all, I am very happy to see too-long overlooked French
> dinosaurs coming back on screen !!
>
> Also, I have some comments to add, regarding this paper. What is not
> stated in the abstr
> subfamily, the Majungasaurinae, as "all the abelisaurids more closely
> related to *Majungasaurus crenatissimus* (Depéret, 1896) Lavocat, 1955
> than to *Carnotaurus sastrei* Bonaparte and Novas, 1985".
>
> While this procedure is perfectly understandable given their
> phylogenetic results, the definition of a subfamily of the Abelisauridae
> created de facto the corresponding subfamily with the same authors
> according to the ICZN. In that case, I wonder if it should not have been
> better to refer to *Abelisaurus* Bonaparte and Novas, 1985 instead of
> *Carnotaurus*.
>
> It would have facilitated the taxonomy of abelisaurids, with:
> 1/ A clade of taxa closer to *Majungasaurus* than to *Abelisaurus*
> 2/ A second clade of taxa closer to *Abelisaurus* than to *Majungasaurus*
> 3/ A grade of taxa that are as close to the former than to the latter
> genera.
>
> I am not as familiar with the PhyloCode as with the ICZN, but isn't
> there some rule - or at least some recommendation - that would be
> relevant in this case ?
>
> What do you think ?
>
> Cheers,
> Jocelyn
>
> Le 13/12/2013 17:55, Ben Creisler a écrit :
>> From: Ben Creisler
>> bcreisler@gmail.com
>>
>>
>> A new online paper:
>>
>>
>> Thierry Tortosa, Eric Buffetaut, Nicolas Vialle, Yves Dutour, Eric
>> Turini & Gilles Cheylan (2013)
>> A new abelisaurid dinosaur from the Late Cretaceous of southern
>> France: Palaeobiogeographical implications.
>> Annales de Paléontologie (advance online publication)
>> doi: http://dx.doi.org/10.1016/j.annpal.2013.10.003
>> http://www.sciencedirect.com/science/article/pii/S075339691300089X
>>
>> The Abelisauridae are a family of mainly Cretaceous theropod dinosaurs
>> with a wide distribution across the Gondwanan land masses. Although
>> their presence in Europe was reported twenty-five years ago, it has
>> often been considered as controversial largely because of the
>> incompleteness of the available specimens. We report here the
>> discovery of well-preserved abelisaurid material, including a highly
>> diagnostic br

>> in the Aix-en-Provence Basin, near the eponym city in south-eastern
>> France. A new abelisaurid taxon is erected, Arcovenator escotae gen.
>> nov., sp. nov., on the basis of cranial and postcranial material. A
>> phylogenetic analysis reveals that the new Abelisauridae from Provence
>> is more closely related to taxa from India and Madagascar than to
>> South American forms. Moreover, Genusaurus, Tarascosaurus and the
>> previous Late Cretaceous discoveries are identified as basal
>> abelisaurids. Contrary to previously proposed palaeobiogeographical
>> models of abelisaurid evolution, the presence of the new taxon in
>> Europe suggests that Europe and Africa may have played a major role in
>> abelisaurid dispersal, which apparently involved crossing marine
>> barriers.
>>
>
>
> --
> "As a Professor of Science, I assure you we did in fact evolve from
> filthy monkey men." Hubert J. Farnworth.                                      
>