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Albertaceratops and other new papers



From: Ben Creisler bh480@scn.org

In case these items have not been mentioned yet:

A NEW BASAL CENTROSAURINE CERATOPSID FROM THE OLDMAN FORMATION,
SOUTHEASTERN ALBERTA
MICHAEL J. RYAN 
Journal of Paleontology  81(2): 376?396 (2007)

Abstract: A new centrosaurine ceratopsid, Albertaceratops nesmoi, is
described from the lower Oldman Formation (Upper Cretaceous) of southern
Alberta, and is based on a single, almost complete skull. Referred material
is described from equivalent beds in the Judith River Formation of
north-central Montana. A limited phylogenetic analysis of the Ceratopsidae
places the new taxon as the basal member of the Centrosaurinae and
indicates that robust, elongate postorbital horncores that form a
synapomorphy of (Ceratopsidae + Zuniceratops) are also present in
Centrosaurinae


REDESCRIPTION AND PHYLOGENETIC POSITION OF CAYPULLISAURUS (ICHTHYOSAURIA:
OPHTHALMOSAURIDAE)
MARTA FERNÁNDEZ 
Journal of Paleontology.  81(2): 368?375 (2007)
Abstract: The ophthalmosaurid Caypullisaurus from the Late Jurassic?Early
Cretaceous of the Neuquén Basin, Argentina, is redescribed based on new
information from recent discoveries. Cladistic analysis of Caypullisaurus,
based on previous ichthyopterygian data sets and using NONA, yielded two
most parsimonious trees. Two clades are recognized within the
Ophthalmosauridae. Caypullisaurus is found to be nested with
Brachypterygius and Platypterygius. Simultaneous, unconstrained analysis,
using unambiguous character optimization, is suggested as the best way to
analyze data sets with large amounts of missing data.

AN OSSIFIED TENDON TRELLIS IN CHASMOSAURUS (ORNITHISCHIA: CERATOPSIDAE)
ROBERT HOLMES AND CHRISTOPHER ORGAN
Journal of Paleontology  81(2) 368?375 (2007)

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Redescription of Aigialosaurus dalmaticus Kramberger, 1892, a Cenomanian
mosasauroid lizard from Hvar Island, Croatia

Alex R. Dutchak and Michael W. Caldwell 
Canadian Journal of Earth Sciences i43(12): 1821-1834 (2006) 


Abstract: Redescription of the type and only specimen of Aigialosaurus
dalmaticus (BSP 1902II501), an "aigialosaurian" squamate from the
Cenomanian?Turonian of Hvar, Croatia, and, at the time of collection, the
Italian island of Lesina, indicates that previous reviews of the specimen
include erroneous anatomical interpretations. The type specimen presents a
new and unique pelvic anatomy: the ilium of A. dalmaticus is an elongate
element with well-developed anterior and posterior iliac processes. A
scenario is presented for mosasaurid pelvic evolution, whereby the
anteriorly elongate and dorsally directed ilium of mosasauroids is not
derived from the forward rotation of the posterior iliac process, but
rather the reduction of that process and the elaboration of the anterior
iliac process. Recent phylogenetic analysis of Mosasauroidea finds A.
dalmaticus to be the sistergroup to Opetiosaurus bucchichi and all other
mosasaurids and "aigialosaurs." We examine the character state assignments
for A. dalmaticus in that study and refute those assignments owing to the
absence of preservation of all four characters states found to separate A.
dalmaticus from O. bucchichi. 


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