MACNBR   00242
MUSEO ARGENTINO DE CIENCIAS NATURALES "BERNARDINO RIVADAVIA"
Unidad Ejecutora - UE
capítulos de libros
Título:
MIDDLE EOCENE - OLIGOCENE GASTROPODS OF THE SARMIENTO FORMATION, CENTRAL PATAGONIA
Autor/es:
MIQUEL, S.E.; BELLOSI, E.S.
Libro:
The Paleontology of Gran Barranca: Evolution and Environmental Change through the Middle Cenozoic of Patagonia
Editorial:
Cambridge University Press
Referencias:
Lugar: Cambridge (UK); Año: 2009; p. 63 - 70
Resumen:
Diverse fossil gastropodsare preserved in the lower and middle sections of the continental Sarmiento Formation in Chubut province, Argentina. The assembklage is dominated by land specimens assigned to five families (15 genera). A new genus and species of Charopidae is described. the presence of Austroborus sp. (Strphocheilidae) and Plagiodontes sp (Odontostomidae) is noted for the first time. Stratigraphic distribution and ecological affinities with related living specimens allow us to infer that warm-temperate and humid environments prevailed in the late middle Eocene (Casamayoran SALMA), with species of Strophocheilidae, Orthalicidae and Chilinidae. In the Mustersan SALMA (middle-late Eocene) a significant increase in diversity is observed, mostly dominated by Charopidae, which indicates cooler conditiones in accordance with the global climatic trend. The fauna preserved in deseadan SALMA beds (late Oligocene) is similar but lessdiverse than the Casamayoran fauna, indicating a return to probably locally wetter and warmer conditions.