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Wilson, J. A. 2005. Redescription of the Mongolian sauropod Nemegtosaurus mongolienesis Nowinski (Dinosauria: Saurischia) and comments on Late Cretaceous sauropod diversity. Journal of Systematic Palaeontology 3:283-318.

ABSTRACT: The isolated skulls of Nemegtosaurus mongoliensis and Quaesitosaurus orientalis from the Nemegt Basin of Mongolia are among the most complete sauropod cranial remains known from the Late Cretaceous, yet their evolutionary relationships to other neosauropods have remained uncertain. Redescription of the skull of Nemegtosaurus identifies key features that link it and its closely related counterpart Quaesitosaurus to titanosaur sauropods. These include a posterolaterally orientated quadrate fossa, 'rocker'-like palatobasal contact, pterygoid with reduced quadrate flange and a novel basisphenoid-quadrate contact. Other features are exclusive to Nemegtosaurus and Quaesitosaurus, such as the presence of a symphyseal eminence on the external aspect of the premaxillae, a highly vascularised tooth bearing portion of the maxilla, an enclosed 'maxillary canal', orbital ornamentation on the postorbital, prefrontal and frontal, exclusion of the squamosal from the supratemporal fenestra and dentary teeth smaller in diameter than premaxillary and maxillary teeth.
Re-examination of Late Cretaceous sauropod distributions in the light of this well-supported phylogenetic hypothesis has important implications for their diversity at the end of the Mesozoic in Asia and elsewhere. Cretaceous Asian sauropod faunas consist solely of titanosauriforms, which probably migrated there from other landmasses during the Late Jurassic, during which time neosauropods were absent from Asia. Globally, narrow-crowned titanosaurs and rebbachisaurids radiated during the Cretaceous, but only titanosaurs survived into the latest Cretaceous. These late-surviving sauropods flourished on most continental landmasses until the end of the Maastrichtian.

Wilson, J. A., Malkani, M. S., and Gingerich, P. D. 2005. A sauropod braincase from the Pab Formation (Upper Cretaceous, Maastrichtian) of Balochistan, Pakistan. Gondwana Geological Magazine, Special Volume 8:101-109.

ABSTRACT: Recent geological and paleontological exploration in the Pab Formation (Upper Cretaceous) of Balochistan Province has uncovered new terrestrial vertebrate remains. Together with Cretaceous vertebrates from India, the Pab vertebrates provide information about the paleobiogeographic history of Indo-Pakistan during its northward migration towards Asia. Vertebrate remains collected from several localities in the Pab Formation include numerous, isolated postcranial bones attributable to titanosaur
sauropods and a well-preserved sauropod braincase that is described here.
The Pab braincase is referable to Eusauropoda, but it does not preserve characteristics diagnostic of lower level sauropod clades. The Pab braincase is relatively
small and diagnosed by a prominent supraoccipital wedge, pronounced proatlantal facets, and a ventrally deflected occipital condyle that forms a 120° angle with
the skull roof. Sauropod braincase material collected from Lameta Formation localities in India (Bara Simla, Dongargaon) closely resembles the Pab braincase in size and general morphology and shares one or more of its diagnostic features. The Indian and Pakistani braincases likely represent the same genus or species, which was distributed across Indo-Pakistan during the Cretaceous. Further exploration in both countries will better constrain the distribution of these and other vertebrate fossils, providing a clearer picture of the Cretaceous vertebrate fauna of Indo-Pakistan.

Bojar, A.-V., Grigorescu, D., Ottner, F., and Csiki, Z. 2005. Palaeoenvironmental interpretation of dinosaur- and mammal-bearing continental Maastrichtian deposits, Hateg Basin, Romania. Geological Quarterly 49:205-222.

Dalla Vecchia, F. M., Morgante, G., and Raponi, D. 2005. Le orme di dinosauro nel Cretaceo dei M. Lepini (Latina, Lazio Meridionale) le abbiamo scoperte noi. (We discovered the dinosaur footprints in the Cretaceous of Mts. Lepini, Latium Region, Italy!) Natura Nascosta 30:8-15.

Dalla Vecchia, F. M. 2005. Un viaggio geo-paleontologico in Marocco (A geopaleontological trip to Morocco). Natura Nascosta 30:16-44.

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

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