Megatherioidea (Mammalia, Xenarthra, Tardigrada) from the Pinturas Formation (Early Miocene), Santa Cruz Province (Argentina) and their chronological implications

BRANDONI, D.; GONZÁLEZ RUIZ, L. R.; TEJEDOR, M. F.; MARTIN, G.; FLEAGLE, J. G.

PALAEONTOLOGISCHE ZEITSCHRIFT

SPRINGER HEIDELBERG

Lugar: HEIDELBERG; Año: 2016 vol. 90 p. 619 - 628

0031-0220

Pyroclastic and epiclastic continental sediment bearing the ??fauna Astrapothericulense?? from the Pintura Formation of Ameghino crop out mainly at several localitie at the upper valley of the Pinturas River and itstributaries, northwestern Santa Cruz Province, Argentina These continental sediments are referred to the Burdigalia Stage and constitute the basis for the recognition of th Pinturas Formation. The fauna recorded in the Pintura Formation mainly consists of mammals, specially rodents native ungulates, xenarthrans and primates. Here w describe the first association of Megatherioidea (Mammalia Xenarthra, Tardigrada) from different localities o the Pinturas Formation with accurate geographic an stratigraphic provenance. The Megatherioidea from th Pinturas Formation presented herein are represented by (1) Schismotherium cf. binum; (2) Hapalops sp.; and (3) megatherioidea indet. In addition, the holotypes of Schismotheriu binum (MACN A 11750), Hapalops curvu (MACN A 11140), and Pelecyodon arcuatus wer collected from the ??fauna Astrapothericulense?? o Ameghino; unfortunately, it is not easy to determine if they were collected from the Pinturas Formation since they ar part of Ameghino?s Collection (MACN), but were collecte a time when the Pinturas Formation had not yet been proposed. The presence of a species of Schismotherium and of Hapalops in the Pinturas Formation represent accurate early records for these genera, but not necessarily th earliest. The age of the Pinturas Formation could overlap partially or totally, with the age of the Santa Cruz Formatio at the Atlantic coast, where most Early Miocene Megatherioidea were collected.