[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Anhanguera and Anhangueridae

Alexander Kellner sent me the following e-mail from the dinosaur mail list:

'Dear Colleagues,

Hebert Bruno Campos recently sent me a message posted to this list by David 
regarding the problematic of Anhanguera and the Anhangueridae. Although I do
not want to use this list to make an extensive debate on this topic, I would
like to make some brief comments.

The genus Anhanguera was proposed by Campos and Kellner (1985) on a complete
skull from the Santana Formation that was designated A. blittersdorffi. The
clade Anhangueridae is defined as the most common ancestor of Anhanguera
(blittersdorffi) and Tropeognathus (mesembrinus) and all their descendants.

There are authors that assigned several species of the Santana Formation to
genera found in the Cambridge Greensand. I am not sure how many of you have
worked or read papers on the specimens from the CG deposit, but the material
is far from being complete: the expression "fragmentary" can be considered a
compliment to most specimens, including the type material of Ornithocheirus
compressirostris and Criorhynchus simus. There are authors that regard the
genus Ornithocheirus as a senior synonym of Criorhynchus and others that
treat them separately. The same happens with Coloborhynchus X Criorhynchus,
making the nomenclature situation of the Cambridge Greensand material a
problem difficult to resolve. Considering Ornithocheirus and Criorhynchus
synonymous was the only possibility for some to created a new "family" - the
Lonchodectidae - to classify most taxa that others have classified in the
Ornithocheiridae, increasing the already confuse and problematic taxonomy of
those taxa rather than solving it.

In any case, there is a great deal of interpretation if one should or not
assign a species to a previously established genus. The assignment of
species found in the Santana Formation to Coloborhynchus, Criorhynchus or
Ornithocheirus is not evident (particularly because of the incompleteness of
the Cambridge Greensand material) and has still to be demonstrated.
Fastnacht (2001) has written an interesting paper that addresses part of
this question. It is amazing how much differences he could come up with
comparing the bits of premaxillae with the Santana material. I invite
everyone to judge for himself what to make of those morphological
differences (and others like paleogeography and the different ages of the
Santana and the Cambridge Greensand deposits).

In any case, I want to point out to everyone working with pterosaur
phylogeny and taxonomy that there are different ideas out there. Mine you
can see in the following (not always cited) papers listed bellow.


Alexander Kellner

KELLNER, A. W. A. 1990. Os répteis voadores do Cretáceo Brasileiro. In:
Anuário do Instituto de Geociências, CCMN, UFRJ, ano 1989, p. 86-106.

KELLNER, A. W. A. 1994. Remarks on pterosaur taphonomy and paleoecology.
Acta Geologica Leopoldensia, 39 (1): 175-189.

KELLNER, A.W.A. 1996. Description of new material of Tapejaridae and
(Pterosauria, Pterodactyloidea) and discussion of pterosaur phylogeny, Ph.D.
Columbia University (available through UMI - University Microfilms
International/ ProQuest).

KELLNER, A.W.A. & TOMIDA, Y. 2000. Description of a new species of
Anhangueridae (Pterodactyloidea) with comments on the pterosaur fauna from
the Santana Formation (Aptian-Albian), Northeastern Brazil. National Science
Museum Monographs, 17: 1-135.

KELLNER, A. W. A. 2001. New hypothesis of Pterosaur Phylogeny. In: Barros,
L. M., Nuvens, P. C. & Filgueira, J. B. M. (eds.) I e II Simpósios sobre a
Bacia do Araripe e bacias interiores do Nordeste, Comunicações. Crato, p.

KELLNER, A.W.A. 2003. Pterosaur phylogeny and comments on the evolutionary
history of the group. In: Buffetaut, E. & Mazin, J.M. (eds). Evolution and
Paleobiology of Pteroaurs. Geological Society, Special Publication 217,p.