INIBIOMA   20415
INSTITUTO DE INVESTIGACIONES EN BIODIVERSIDAD Y MEDIOAMBIENTE
Unidad Ejecutora - UE
artículos
Título:
Paleontological discoveries in the Chorrillo Formation (upper Campanian-lower Maastrichtian, Upper Cretaceous), Santa Cruz Province, Patagonia, Argentina
Autor/es:
FEDERICO. L. AGNOLIN; FEDERICO BRISSON-EGLI; MARTÍN D. EZCURRA; GERARDO ALVAREZ-HERRERA; NICOLÁS R. CHIMENTO; SERGIO E. MIQUEL; VALERIA S. PEREZ LOINAZE; SEBASTIÁN ROZADILLA; MATIAS J. MOTTA; AGUSTÍN G. MARTINELLI; ADRIEL R. GENTIL; JORDI A. GARCÍA-MARSÀ; FÁTIMA F. BRITO; MARIELA S. FERNÁNDEZ; FERNANDO. E. NOVAS; ALEXIS M. ARANCIAGA-ROLANDO; MAURICIO CERRONI; JULIA S. D´ANGELO; SERGIO BOGAN; GASTÓN LO COCO; EZEQUIEL I. VERA; LEONARDO SALGADO
Revista:
Revista del Museo Argentino de Ciencias Naturales
Editorial:
Museo de Ciencias Naturales Bernardino Rivadavia
Referencias:
Lugar: Capital Federal; Año: 2019 vol. 21 p. 217 - 292
ISSN:
0373-9066
Resumen:
The first fossil remains of vertebrates, invertebrates, plants and palynomorphs of the ChorrilloFormation (Austral Basin), about 30km to the SW of the town of El Calafate (Province of Santa Cruz), are described. Fossils include the elasmarian (basal Iguanodontia) Isasicursor santacrucensis gen. et sp. nov., the largetitanosaur Nullotitan glaciaris gen. et sp. nov., both large and small Megaraptoridae indet., and fragments ofsauropod and theropod eggshells. The list of vertebrates is also composed by the Neognathae Kookne yeutensisgen. et sp. nov., two isolated caudal vertebrae of Mammalia indet., and isolated teeth of a large mosasaur. Remainsof fishes, anurans, turtles, and snakes are represented by fragmentary material of low taxonomical value, withthe exception of remains belonging to Calyptocephalellidae. On the other hand, a remarkable diversity of terrestrial and freshwater gastropods has been documented, as well as fossil woods and palinological assemblages. TheChorrillo Formation continues south, in the Las Chinas River valley, southern Chile, where it is called DoroteaFormation. Both units share in their lower two thirds abundant materials of titanosaurs, whose remains cease to appear in the upper third, registering only elasmarians (Chorrillo Formation) and hadrosaurs (DoroteaFormation). Above both units there are levels with remains of invertebrates and marine reptiles. It is strikingthat the dinosaurs of the lower two thirds of the Chorrillo and Dorotea formations are represented by largebasal titanosaurs and Megaraptoridae coelurosaurs, being the Saltasaurinae and Aeolosaurinae sauropods andAbelisauridae theropods totally absent. In contrast, these taxa are dominant components in sedimentary units ofcentral and northern Patagonia (e.g., Allen, Los Alamitos, La Colonia formations). Such differences could reflect,in part, a greater antiquity (i.e., late Campanian-early Maastrichtian) for the Chorrillo fossils, or, more probably,different environmental conditions. Thus, knowledge of the biota of the southern tip of Patagonia is expanded,particularly those temporarily close to the K-Pg boundary