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New in CJES
The latest issue of _CJES_ keeps the tradition of late-year dinosaur papers
flowing, but because this list is a diverse bunch, there are interesting
non-dinosaurian papers in there, was well.
Zhou Z.-h., L. M. Chiappe & Zhang F.-c. 2005. Anatomy of the
Early Cretaceous bird *Eoenantiornis buhleri* (Aves:
Enantiornithes) from China. _Canadian Journal of Earth Sciences
- Revue de canadienne sciences du Terre_ 42(7):1331-1338.
"A detailed description of the anatomy, in particular of the
skull, of *Eoenantiornis* is provided. This description reveals
many morphological characters previously unknown for
enantiornithine birds, such as presence of a distinct facet for
the intramandibular articulation between the dentary and
postdentary bones. *Eoenantiornis* documents an intermediate
stage in the abbreviation of the alular digit among
Ornithothoraces, which paralleled a similar transformation
within Ornithuromorpha. Our analysis also indicates that
*Eoenantiornis* belongs to the Euenantiornithes."
Mickey Mortimer can probably say more about this paper than I can.
Müller, J. 2005. The anatomy of *Askeptosaurus italicus* from
the Middle Triassic of Monte San Giorgio and the
interrelationships of thalattosaurs (Reptilia, Diapsida).
_Canadian Journal of Earth Sciences - Revue de canadienne
sciences du Terre_ 42(7):1347-1367.
"The anatomy of the thalattosauriform reptile *Askeptosaurus
italicus* from the Middle Triassic of Monte San Giorgio is
redescribed. Important anatomical features are the
plesiomorphic braincase, the unique fronto-lacrimal contact,
the absence of a previously described thyroid fenestra, and
significant intraspecific variation in the carpus. An analysis
of thalattosaur ingroup relationships reveals that
*Endennasaurus* and the monophyletic *Askeptosaurus* and
*Anshunsaurus* are the sister group to all other thalattosaurs,
whereas the Monte San Giorgio taxa *Clarazia* and *Hescheleria*
form the sister clade of *Thalattosaurus*, and the Chinese
*Xinpusaurus* and the Californian *Nectosaurus* form a
monophyletic group. The analysis supports the biogeographic
interpretation of trans-Pacific relationships and a re-invasion
of Tethyan areas."
While I have not seen this paper, this other paper from _AMNOvitates_ is also
Liu J. & O. Rieppel. 2005. Restudy of *Anshunsaurus
huangguoshuensis* (Reptilia: Thalattosauria) from the Middle
Triassic of Guizhou, China. _American Museum Novitates_ 3488:
"We here describe the complete skeletal anatomy of *Anshunsaurus
huangguoshuensis* that previously remained unknown. The
description includes a review of the dorsal side of the skull
as well as the first description of the ventral side of the
skull and of the postcranial skeleton. A new phylogenetic
analysis supports the monophyly of Askeptosauridea and
Thalattosauridea; *Endennasaurus* is found to be closely
related to Askeptosauridae."
Irmis, R. B. & W. G. Parker. 2005. Unusual tetrapod teeth from
the Upper Triassic Chinle Formation, Arizona, USA. _Canadian
Journal of Earth Sciences -- Revue de canadienne sciences du
"Two teeth collected from the Upper Triasssic Chinle Formation
of northeastern Arizona are described here and named
*Kraterokheirodon colberti* gen. et sp. nov. These teeth are
novel in having an occlusal ridge with six cusps and a
posterior shelf lacking dentine. Evidence for thecodont
implantation of the root suggests amniote affinities for these
teeth. They do not match any teeth known for basal vertebrates
or basal tetrapods. Although the teeth display some affinities
with "traversodont" cynodonts, there are significant
differences that preclude a referral to this group. These teeth
most probably represent an unknown tetrapod clade and document
the presence of a large amniote previously unknown from Late
Triassic terrestrial faunas."
This paper was made available to me by accident some time ago, so I am glad
to see it published so that I may talk about it. I must say, I have to agree
that the tooth they describe is so quite unusual that it literally defies
corellative interpretation! The name, incidentally, derives from the words
*krater* for "cup", *kheiron* for "hand" and *odon* for "tooth," because the
tooth looks like a hand forming a cupping motion, with an array of serrae
around the basal rim looking like a thumb, and the shape of the primary crest
of the crown resembling the other fingers. This seems to be a non-mammal tooth
mimicking the talonid of tribosphenic mammals, as well as the ankylosaur and
leptoceratopid tooth morphotypes in enforcing an occlusal relationship between
upper and lower teeth, as a mortar and pistil arrangement. Very cool.
Ryan, M. J. & A. P. Russell. 2005. A new centrosaurine
ceratopsid from the Oldman Formation of Alberta and its
implications for centrosaurine taxonomy and systematics.
_Canadian Journal of Earth Sciences -- Revue de canadienne
sciences de Terre_ 42(7):1369-1387.
"*Centrosaurus brinkmani* (sp. nov) is distinguished from
*Centrosaurus apertus* by key features of its cranial
ornamentation, including the shape and orientation of the
postorbital horn and parietal ornamentation at parietal locus
3, the shape of the parietal ornamentation at locus 2, and the
possession of accessory parietal ossifications developed as
short spines on the caudal parietal ramus. This species is
restricted to the Oldman Formation of southern Alberta and is
the oldest ceratopsid represented by diagnostic material in
Canada. Phylogenetic analysis of the Centrosaurinae suggests
that the development of spike-like ornamentation at the
parietal locus 3 parietal locus is inversely related to the
development of the P1 parietal ornamentation."
So finally, the "popcorn" centrosaur floating around since SVP 1999 is
finally described. And fortunately, it appears to be a divergent species of
*Centrosaurus* with some wicked frill ornaments. Jordan Mallon probably has
more to say on this critter than I.
Jaime A. Headden
"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)
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