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RE: Sciurimimus, the fuzzy megalosaur



Very cool.  Based on the extensive list of differences from Juravenator in the 
supplementary information, I retract my prior statements this is just another 
specimen of that genus.  Unfortunately, of the three matrices Rauhut et al. 
include Sciurumimus in, only Benson et al.'s is completely coded.  Both Smith 
et al. (2007) and especially Choiniere et al. (2010) leave tons of codings 
unknown when they are very easily determined.  Which makes statements like 
"Choiniere et al. presented one of the largest phylogenetic analyses of 
nonavian theropods published so far, including two outgroup and 92 
neotheropodan ingroup taxa, scored across 421 characters" sadly mistaken.  Note 
that since Rauhut et al. actually did code Sciurumimus completely, the tree of 
Choiniere et al. is suddenly more resolved.

Mickey Mortimer

----------------------------------------
> Date: Mon, 2 Jul 2012 15:27:31 -0400
> From: tholtz@umd.edu
> To: dinosaur@usc.edu
> Subject: Sciurimimus, the fuzzy megalosaur
>
> This just in:
>
> Oliver W. M. Rauhut, Christian Foth, Helmut Tischlinger, and Mark A. Norell
> Exceptionally preserved juvenile megalosauroid theropod dinosaur with
> filamentous integument from the Late Jurassic of Germany
> PNAS 2012 : 1203238109v1-201203238.
>
> Abstract
>
> Recent discoveries in Asia have greatly increased our understanding of the
> evolution of dinosaurs’ integumentary structures, revealing a previously
> unexpected diversity of “protofeathers” and feathers. However, all
> theropod dinosaurs with preserved feathers reported so far are
> coelurosaurs. Evidence for filaments or feathers in noncoelurosaurian
> theropods is circumstantial and debated. Here we report an exceptionally
> preserved skeleton of a juvenile megalosauroid, Sciurumimus albersdoerferi
> n. gen., n. sp., from the Late Jurassic of Germany, which preserves a
> filamentous plumage at the tail base and on parts of the body. These
> structures are identical to the type 1 feathers that have been reported in
> some ornithischians, the basal tyrannosaur Dilong, the basal
> therizinosauroid Beipiaosaurus, and, probably, in the basal coelurosaur
> Sinosauropteryx. Sciurumimus albersdoerferi represents the
> phylogenetically most basal theropod that preserves direct evidence for
> feathers and helps close the gap between feathers reported in
> coelurosaurian theropods and filaments in ornithischian dinosaurs, further
> supporting the homology of these structures. The specimen of Sciurumimus
> is the most complete megalosauroid yet discovered and helps clarify
> significant anatomical details of this important basal theropod clade,
> such as the complete absence of the fourth digit of the manus. The
> dentition of this probably early-posthatchling individual is markedly
> similar to that of basal coelurosaurian theropods, indicating that
> coelurosaur occurrences based on isolated teeth should be used with
> caution.
>
>
> 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