On the presence of Pyramiodontherium (Mammalia, Tardigrada, Megatheriidae) in the “Conglomerado Osífero (late Miocene) of Argentina its paleobiogeographic implicance.

BRANDONI, D., CARLINI, A. A.

Revista Italiana di Paleontologia e stratigrafia

REVISTA ITALIANA DI PALEONTOLOGIA E STRATIGRAFIA

Año: 2009 vol. 115 p. 111 - 123

0375-9784

ABSTRACT The biochron of the subfamily Megatheriinae (typified by Megatherium Cuvier) in Argentina extends from the Middle Miocene of Patagonia to the Late Pleistocene – Early Holocene, reaching their highest diversity in the “Conglomerado osífero” (Late Miocene) of the Entre Ríos Province, northeastern of Argentina. Among the megatheriines that occur in the “Conglomerado osífero”, the genera Promegatherium Ameghino, Eomegatherium Kraglievich and Pliomegatherium Kraglievich seem to represent relatively small to medium-sized taxa. In this work we describe new materials that are assigned to Pyramiodontherium sp. Pyramiodontherium sp. is larger than the other genera from the “Conglomerado osífero” and comparable in size to some Quaternary Megatherium species, like M. sundti (?). Until now, three valid species had been recognized for Pyramiodontherium that were distributed mainly in northwestern Argentina. The genus was recorded for the late Miocene in Catamarca Province (and probably also in Tucumán Province), and for the late Pliocene in La Rioja Province. The presence of this genus in the northeastern of Argentina extends its paleobiogeographycal distribution.