THE DESEADAN LAND MAMMAL AGE IN URUGUAY AND THE REPORT OF SCARRITTIA-ROBUSTA NOV-SP (LEONTINIIDAE, NOTOUNGULATA) IN THE FRAY-BENTOS FORMATION (OLIGOCENE-LOWER MIOCENE)

The first record of Scarrittia outside Argentina is herein presented. New evidence supporting the generic distinction between Scarrittia and Leontinia in mandibular morphology and an emended diagnosis of Scarri ttia is offered: deep lingual groove in the trigonid of m3, size of th e canine intermediate between i3 and pl and shorter symphysial length in contrast to Leontinia. Scarrittia robusta nov. sp. is here diagnose d on the basis of mandibular remains from the Fray Bentos Formation in Uruguay. The new species is distinguished from S. canquelensis by sub parallel and thicker mandibular rami and less procumbent incisors. Thi s new record of Scarrittia in Uruguay widely extends the geographic ra nge of the genus, which was previously known only in Patagonia. The as sociated fossil assemblage and the occurrence of Scarrittia in the Fra y Bentos Formation supports previous referrals of the fauna to the Des eadan Land Mammal Age.