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Re: Ceratopsid Question



----- Original Message -----
From: "John Conway" <john_conway@mac.com>
To: <dinosaur@usc.edu>
Sent: Sunday, March 24, 2002 2:29 PM
Subject: Ceratopsid Question

> Are any members of the Ceratopsidae found outside North America? If so,
> what are they?

As far as I known outside North America  there are no "true" Ceratopsidae
(Centrosaurines e/o Chasmosaurines). However, in 1989 Nessov and Kaznyshkina
described a new genus and species, Turanoceratops tardabilis known from a
left maxilla ( Chigr Museum, Leningrad 251/12457 (HoloType)), and three
maxillae, five horns, a partial scapula, and about 50 teeth ( Chigr Museum,
Leningrad 351/310/12457 (Referred Material)) all this material was collected
from the upper Cretaceous (Maastrichtina) of Jarakuduk, Russia. Nessov and
Cherepanov diagnosed Turanoceratops tardabilis as follows: Nasal horn large,
other horns moderate-sized, sharp; rostral bone and jaw low, rostral with
dull edge; teeth with divided roots, two per row. As described  by Nessov
et. al. the maxilla (if complete) had about 25 teeth and the largest teeth
is 16.5mm in length.
In most phylogenetic analysis Turanoceratops tardabilis is classified as a
Ceratopsomorpha, however, P.J. Makovicky in his 2001 phylogenetic analysis
of basal Ceratopsia excluded Turanoceratops tardabilis because it lacks
diagnostic features, and the identity of many of the referred elements (for
example a misidentified Ornithopod braincase) is questionable.

By
Alessandro Marisa