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New Papers Revolution

Just a few for today:

Casal, G., Martínez, R., Luna, M., Sciutto, J.C., and Lamanna, M. 2007. Aeolosaurus colhuehuapensis sp. nov. (Sauropoda, Titanosauria) de la Formación Bajo Barreal, Cretácico Superior de Argentina. Revista Brasileira de Paleontologia 10(1):53-62.

ABSTRACT: A new sauropod, Aeolosaurus colhuehuapensis sp. nov., based on an articulated caudal series recovered from an emergent island in Lago Colhué Huapi, Chubut Province is described. This series is characterized by neural arches located very anteriorly above the centrum and inclined forward; well-developed prezygapophyses projecting forward and upward, and wide articular facets in the anterior caudals. Aeolosaurus colhuehuapensis sp. nov. is unique by the presence of a marked and deep fossa between the transverse process and the base of the neural spine in the most anterior caudal vertebrae; a slender lamina that connects the base of the prespinal lamina with the lower part of the articular facet in the medial part of the prezygapophysis, defining a fossa on both sides of the prespinal lamina; posterior condyle centrally placed in the entire caudal series. The genus Aeolosaurus is recorded in the Campanian-Maastrichtian in Argentina and Brazil, and is considered part of a faunal association with hadrosaurids, Madtsoiinae, Chelidae, Sudamericidae, and non-tribosphenic Theria in floodplain or littoral environments. Its presence in the Upper Member of the Bajo Barreal Formation, along with other paleontological records from the same locality, and geologic observations allow us to assign preliminarily a Campanian-Maastrichtian? age for the upper levels of this stratigraphic unit outcropping in the southeast of Lago Colhué Huapi, Chubut Province.

Nesbitt, S.J., Irmis, R.B., and Parker, W.G. 2007. A critical re-evaluation of the Late Triassic dinosaur taxa of North America. Journal of Systematic Palaeontology 5(2):209-243. doi: 10.1017/S1477201907002040.

ABSTRACT: The North American Triassic dinosaur record has been repeatedly cited as one of the most complete early dinosaur assemblages. The discovery of Silesaurus from Poland and the recognition that Herrerasaurus and Eoraptor may not be theropods have forced a re-evaluation of saurischian and theropod synapomorphies. Here, we re-evaluate each purported Triassic dinosaur from North America on a specimen by specimen basis using an apomorphy-based approach. We attempt to assign specimens to the most exclusive taxon possible. Our revision of purported Late Triassic dinosaur material from North America indicates that dinosaurs were rarer and less diverse in these strata than previously thought. This analysis concludes that non-dinosaurian dinosauriforms were present in North America in the Late Triassic. Most of the proposed theropod specimens are fragmentary and/or indistinguishable from corresponding elements in the only well-known Triassic theropod of North America, Coelophysis bauri. No Triassic material from North America can be assigned to Sauropodomorpha, because none of the purported 'prosauropod' material is diagnostic. Recent discovery of the skull and skeleton of Revueltosaurus callenderi from Arizona shows that it is a pseudosuchian archosaur, not an ornithischian dinosaur. As a result, other purported North American ornithischian teeth cannot be assigned to the Ornithischia and therefore, there are no confirmed North American Triassic ornithischians. Non-tetanuran theropods and possible basal saurischians are the only identifiable dinosaurs recognised in North America until the beginning of the Jurassic Period.

Mayr, G., Rana, R.S., Sahni, A., and Smith, T. 2007. Oldest fossil avian remains from the Indian subcontinental plate. Current Science 92(9):1266-1269.

ABSTRACT: We describe the oldest fossil avian remains of the Indian subcontinental plate, from the early Eocene of the Vastan Lignite Mine in Gujarat, India. Three incomplete coracoids and two scapulae are assigned to the new taxon Vastanavis eocaena, gen. et sp. nov. The coracoids resemble the corresponding bone of bustards (Otididae), but a reliable assignment is not possible without additional bones. Independent of their phylogenetic affinities the fossils are of potential biogeographic significance, because similar species are unknown from the well-studied Palaeogene avifaunas of Europe and North America.

Jerry D. Harris
Director of Paleontology
Dixie State College
Science Building
225 South 700 East
St. George, UT  84770   USA
Phone: (435) 652-7758
Fax: (435) 656-4022
E-mail: jharris@dixie.edu
and     dinogami@gmail.com

"Trying to estimate the divergence times
of fungal, algal or prokaryotic groups on
the basis of a partial reptilian fossil and
protein sequences from mice and humans
is like trying to decipher Demotic Egyptian with
the help of an odometer and the Oxford
English Dictionary."
-- D. Graur & W. Martin (_Trends
in Genetics_ 20[2], 2004)