New Palaeogene metatherians from the Quebrada de Los Colorados Formation at Los Cardones National Park (Salta Province, Argentina)

FERNICOLA, JUAN C.; CÁRDENAS, MAGALÍ; PAYROLA, PATRICIO; CHORNOGUBSKY, LAURA; GOIN, FRANCISCO J.; ZIMICZ, A. NATALIA; FERNICOLA, JUAN C.; PAYROLA, PATRICIO; CÁRDENAS, MAGALÍ; CHORNOGUBSKY, LAURA; ZIMICZ, A. NATALIA; GOIN, FRANCISCO J.

JOURNAL OF SYSTEMATIC PALAEONTOLOGY

CAMBRIDGE UNIV PRESS

Lugar: Cambridge; Año: 2018 p. 1 - 17

1477-2019

The Quebrada de Los Colorados Formation (Los Cardones National Park,Salta Province, north-western Argentina), is an Eocene?Oligocene unit well representedin the Calchaqu_ı Valley area. Here we describe a new metatherian association recordedfrom the base of this formation, inferred as middle Eocene. Represented taxaare: Sparassodonta, family indet.: Patene simpsoni; Polydolopimorphia,Bonapartheriiformes, Argyrolagoidea: family, genus, and species indet.; and Bonapartherioidea,Prepidolopidae: Punadolops alonsoi and Coloradolops cardonensis gen. et sp.nov. Patene simpsoni is also found in the Tonco Valley, near Los Cardones, andat S~ao Jos_e de Itabora_ı, Rio de Janeiro, Brazil. Punadolops alonsoi wasoriginally described from the Geste Formation in Salta and Catamarca provinces.Hitherto, no other Argyrolagoidea have been found in north-western Argentina inthe Palaeogene. Coloradolops cardonensis is unique to the locality and levelshere described. The preservation of part of the skull constitutes the bestprepidolopid remains known. North-western Argentina is a key region for thestudy of the evolution of South American mammals, since it has a singulargeographical location between the Neotropics and the southernmost part of SouthAmerica. Due to biogeographical constraints, it may lead to a bettercomprehension of the continental distribution of metatherian lineages duringCenozoic times.