New remains of Nothrotheriinae (Mammalia, Xenarthra) from Late Pleistocene fluvial deposits of Northern Pampa (Santa Fe Province, Argentina)

VEZZOSI, RAÚL I.; BRANDONI, DIEGO; BRUNETTO, ERNESTO; ZALAZAR, MARÍA CECILIA

JOURNAL OF SOUTH AMERICAN EARTH SCIENCES

PERGAMON-ELSEVIER SCIENCE LTD

Año: 2019 vol. 89 p. 47 - 54

0895-9811

In this contributionthe record of a Nothrotheriinae (Xenarthra, Tardigrada) ground sloth isreported from the Late Pleistocene of the Northern Pampa of Santa Fe Province,Argentina. The stratigraphic unit where the fossil was collected corresponds tofluvial-palustrine sediments of the Timbúes Formation, outcropping along the CarcarañáRiver valley. The relative stratigraphic position of this lithostratigraphicunit, observed in several sections mainly on the Paraná River cliffs nearCarcarañá River distal area, suggests that it was deposited during the LastInterglacial Stage.The specimen (MPAHND-135),assigned to Nothrotherium cf. torresi, is represented by the proximal two-thirds of a left femur thatshows a prominent lesser trochanter and no connection between the thirdtrochanter and the ectepicondyle. The presence of Nothrotherium cf. torresiin sediments related to humid conditions supports the idea that Nothrotheriinaehad great ecological tolerance and was capable of inhabiting climates rangingfrom cold and arid, as was previously proposed, to warm and humid.