First postcranial record of Didelphis sp. (Didelphidae, Mammalia) in the Pleistocene of Chacopampean region, Argentina.

VEZZOSI, R. I.

Mendoza

Congreso; The 10th International Mammalogical Congress.; 2009

Biodiversity Research Group-GIB-Institute for Aridlands Research-IADIZA;Center for Science & Technology Mendoza-CCT; National Council of Science and Technology-CONICET; International Federation of Mammalogists-IFM-SAREM

The marsupials are among the oldest mammals in South America. In particular the didelphoids are the most generalizad of Neogenedidelphimorphians and represent the largest group to the present. In relation with the fossil record, the oldest known species of thegenus Didelphis sp. comes from the late Miocene deposits of Brazil. In Argentina Didelphinae subfamily is well represented in Plio-Pleistocene deposits in the pampa region, through two extinct species D. crucialis (late Pliocene) and D. eregi (late Pliocene-earlyPleistocene). The living species D. albiventris appear since the latest Pleistocene in South America (age/state Lujanian). The purposeof the present contribution is to promote a new material assigned to Didelphis sp. in sediment certainly relate, from the mammalfauna association, to the Pleistocene s.l. Carriers crop levels in the town of Manucho, Departamento La Capital, Santa Fe province.Geo-paleontological studies now underway will clarify, in the future, the age of this fauna association. The specimen consists of acomplete humerus (MFA-PV sin Nº). This is the first poscraenal fossil record of Didelphidae within the chacopampean region in thePleistocene of Santa Fe. Currently this family is widely distributed and presents a great tolerance to diverse habitats conditions, fromsubtropical rainforest to open settings (grasslands, even deserts), along natural and artificial forests. From a paleoenvironmentalpoint of view, based on fossil fauna found in the area, could be inferred similar circumstances to savannah woodlands.