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New refs (Euoplocephalus, Spinosaurus)
From: Ben Creisler email@example.com
Here are some rew and recent refs which I don't recall seeing mentioned.
VICKARYOUS, M.K. and A.P. RUSSELL, 2003. A redescription of the skull of
Euoplocephalus tutus (Archosauria: Ornithischia): a foundation for
comparative and systematic studies of ankylosaurian dinosaurs. Zoological
Journal of the Linnean Society. 137 (1): 157 - 187. (January 2003).
Euoplocephalus tutus Lambe (1902) from the Late Cretaceous of North
America, was the first ankylosaurian dinosaur known from significant
cranial material. Previous descriptions of this and other members of the
Ankylosauria have been constrained by a paucity of material and an
extremely apomorphic skull architecture, including the pervasive
development of an embossing osseous ornamentation, and the absence of
traditional morphological landmarks. A relative abundance of more recently
collected and prepared cranial material attributable to Euoplocephalus
enables a reappraisal of this taxon (including the type specimen), and
permits it to be employed as a morphological representative of the clade.
In recognition of previous difficulties encountered due to peculiarities of
ankylosaurian anatomy, a fresh descriptive approach is necessitated.
Herein, the skull is subdivided into five mutually exclusive topographic
regions, within which individual elements are assigned with the assistance
of outgroup comparison. Euoplocephalus is characterized by a distinctive
pattern of cranial sculpturing across the preorbital area, relatively
small, variably fluted teeth lacking a cingulum, a modified palpebral and a
shallow nasal vestibule. Among ankylosaurine ankylosaurs, Euoplocephalus is
unique in having medially inflected maxillary tooth rows. Osteological
evaluation of the type skull of Anodontosaurus lambei Sternberg, 1929
supports its placement into synonymy with Euoplocephalus.
Buffetaut-E & M. Ouaja, 2002. A new specimen of Spinosaurus (Dinosauria,
Theropoda) from the Lower Cretaceous of Tunisia, with remarks on the
evolutionary history of the Spinosauridae
BULLETIN DE LA SOCIETE GEOLOGIQUE DE FRANCE. 173 (5) : 415-421.
AB: A newly discovered incomplete dinosaur dentary from the Chenini
Sandstones (early Albian) of Jebel Miteur (Tataouine Governorate, southern
Tunisia) is extremely similar to the corresponding part of the type of
Spinosaurus aegyptiacus STROMER, 1915, and is identified as Spinosaurus cf.
aegyptiacus. A review of African spinosaurids shows that baryonychines were
present in the Aptian, and apparently became replaced by spinosaurines in
the Albian and Cenomanian, perhaps as part of a more general faunal change
between the Aptian and Albian. Spinosaurines may have been derived from the
less advanced baryonychines. Several alternative hypotheses about the
biogeographical history of the Spinosauridae are discussed.
Buffetaut, E., 2002. Giant ground birds at the Cretaceous-Tertiary
boundary; extinction or survival?
In: Catastrophic events and mass extinctions; impacts and beyond. Special
Paper - Geological Society of America. 356: 303-306. 2002.
A family of giant, flightless ground birds, the Gastornithidae, has been
known for a long time from the early Tertiary (late Paleocene to middle
Eocene) of both Europe and North America. The giant ground bird
Gargantuavis was recently described from the Upper Cretaceous (probably
early Maastrichtian) of France. The question may therefore be asked whether
there is any close phylogenetic relationship between Gargantuavis and the
Gastornithidae, which would suggest survival of giant birds across the
Cretaceous-Tertiary boundary. A close anatomical comparison, however,
reveals that Gargantuavis is a much more primitive bird than the
Gastornithidae, and that they do not belong to the same lineage,
resemblances probably being due to convergent adaptation to a similar mode
of life. Although it cannot be demonstrated at the moment that Gargantuavis
became extinct at the Cretaceous-Tertiary (K-T) boundary, this is a
distinct possibility. If this is the case, the mass extinction of the K-T
boundary will appear to have stopped early giantism and flightlessness in
birds; these were followed by renewed and similar giantism and
flightlessness in a different group of birds in the Paleocene.
Arnold E.N., Azar D., Ineich, I & Nel, A. 2002. The oldest reptile in
amber: A 120 million year old lizard from Lebanon. Journal of
Zoology-London. 258 (1): 7-10. (September, 2002)
Animals enclosed in amber often provide a unique insight into their surface
structure. Such fossils of reptiles are rare and usually not extremely
ancient, the earliest being no more than 40 million years (my). A recently
discovered 120 my lizard from the Lower Cretaceous of Lebanon provides
direct evidence that several common external features of autarchoglossan
lizards had evolved by this time. Ecomorphology indicates that the lizard
concerned had considerable climbing ability on open surfaces and perhaps in
vegetation, and probably lived in a mesic forested environment, something
supported by associated plant and invertebrate remains. [Baabdasaurus
Comment: Fun to speculate about finding a baby pterosaur or climbing
theropod in amber one day at this site.......
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