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Re: Kellner revises Pteranodon: new genera

Dawndraco?  Named after Dawn French?  Surely not after Aurora....

Ronald Orenstein 
1825 Shady Creek Court
Mississauga, ON
Canada L5L 3W2

On 2010-12-16, at 12:24 PM, "Thomas R. Holtz, Jr." <tholtz@umd.edu> wrote:

> http://www.scielo.br/scielo.php?script=sci_abstract&pid=S0001-37652010000400025&lng=pt&nrm=iso&tlng=en
> KELLNER, Alexander W.A.. Comments on the Pteranodontidae (Pterosauria, 
> Pterodactyloidea) with the description of two new species.
> An. Acad. Bras. CiÃnc. [online]. 2010, vol.82, n.4, pp. 1063-1084. ISSN 
> 0001-3765.  doi: 10.1590/S0001-37652010000400025.
> Abstract
> Considered one of the best known flying reptiles, Pteranodon has been subject 
> to several reviews in the last century. Found
> exclusively in the Upper Cretaceous Niobrara Formation and Pierre Shale Group 
> 11 species have been attributed to this genus
> (excluding the ones presently regarded as representing Nyctosaurus). While 
> reviewers agree that this number is inflated, there is
> disagreement on how many species can be identified. The last review 
> recognized only two species (Pteranodon longiceps and Pteranodon
> sternbergi) both being sexually dimorphic. Based on several cranial features, 
> some specimens previously referred to the genus
> Pteranodon are re-evaluated leading to the recognition of the following 
> species, two of which new that are described here:
> Pteranodon longiceps, Geosternbergia sternbergi, Geosternbergia maiseyi sp. 
> nov., and Dawndraco kanzai gen. et sp. nov. They differ
> mainly by features such as the direction and extension of the frontal crest, 
> the angle and extension of the posterior process of the
> premaxillae, the shape and extension of the lower temporal fenestra and the 
> length and proportion of the rostrum. The procedures to
> recognize a pterosaur species are also discussed here, and must take into 
> account primarily morphology, in conjunction with
> stratigraphic and geographic data. Although well aware that changes in 
> morphology not always reflect taxonomy, the lack of
> stratigraphic data and the limited number of specimens that can be 
> confidently assigned to one species hampers our understanding on
> the morphological variations as a function of ontogeny, individual variation 
> and sexual dimorphism. Although the present study has
> not eliminated the possibility to recognize such differences, caution is 
> needed before models are generalized for pterosaurs.
> Pdf at:
> http://www.scielo.br/pdf/aabc/v82n4/25.pdf
> PS, a request: if this thread morphs into a discussion on etymology, PLEASE 
> change the subject line!!
> Thomas R. Holtz, Jr.
> Email: tholtz@umd.edu    Phone: 301-405-4084
> Office: Centreville 1216            
> Senior Lecturer, Vertebrate Paleontology
> Dept. of Geology, University of Maryland
> http://www.geol.umd.edu/~tholtz/
> Fax: 301-314-9661        
> Faculty Director, Science & Global Change Program, College Park Scholars
> http://www.geol.umd.edu/sgc
> Fax: 301-314-9843
> Mailing Address:    Thomas R. Holtz, Jr.
>            Department of Geology
>            Building 237, Room 1117
>            University of Maryland
>            College Park, MD 20742 USA