Late Cretaceous terrestrial vertebrates from the James Ross Basin, West Antarctica

REGUERO, M. A.,; TAMBUSSI, C. P.; CORIA, R.; MARENSSI, S.

JOURNAL OF THE GEOLOGICAL SOCIETY

GEOLOGICAL SOC PUBL HOUSE

Lugar: Londres; Año: 2012 p. 1 - 35

0016-7649

The fossil record of terrestrial vertebrates from the Late Cretaceous of Antarctica isreviewed. This record is composed solely by non-avian and avian dinosaurs and comeexclusively from the marine sediments of the James Ross Basin, Antarctic Peninsula (WestAntarctica). Although three dinosaurian assemblages (Late Campanian, Early Maastrichtianand Late Maastrichtian) are known, the record is still very patchy, and any evolutionaryscenario based on it should be seen as tentative. At least ten taxa of non-avian come fromConiacian to Maastrichtian deposits and at least five avian dinosaurs have been reported ordescribed exclusively from the Maastrichtian from the James Ross Basin. Additional nonaviandinosaur evidence from the same area is based upon the occurrence of LateMaastrichtian sauropod? footprints of Snow Hill Island. New discoveries from the LateCampanian Santa Marta Formation provide much needed data on dinosaur distributionacross Gondwana. The Late Campanian/Early Maastrichtian non-avian dinosaurs (ankylosaurs, ornithopods and theropod dromaeosaurids) groups probably attained a nearcosmopolitandistribution before the Late Cretaceous, and some aspects of this hallmark?Gondwanan? fauna may therefore reflect climate-driven provinciality, not vicariantevolution driven by continental fragmentation. Antarctic Late Cretaceous avian dinosaursare rare and they are restricted to the Maastrichtian and consist in a cariamid?, gaviids, acharadriiform, and Vegavis, a basal Anseriformes. They provide the first strong evidencefor a basal part of the extant avian radiation in the Cretaceous