Systematic revision of Antepithecus brachystephanus Ameghino, 1901, and dental eruption sequence in Eocene “notopithecines” (Notoungulata) from Patagonia

摘要: Abstract In this contribution, a detailed systematic study of all species previously placed into the genus Antepithecus, Barrancan (middle Eocene) “notopithecine” from Patagonia, is performed. addition, other described by Ameghino were studied and are also included in taxon. The comparative morphological description allows corroborating introducing new synonyms, recognizing one valid species, Antepithecus brachystephanus. Its diagnosis expanded number specimens referred to significantly increased. Morphological ontogenetic variations dentition recognized compared with “notopithecines”. A particular eruption sequence permanent premolars ascertained for Patagonian taxa Notopithecus, Transpithecus. These three Casamayoran “notopithecines” have their upper lower milk molars replaced posterior-anterior direction, P/p4, P/p3, P/p2, contrasting notoungulates, including Mustersan Guilielmoscottia. This peculiar its heterogeneity within group could reflect relevant phylogenetic character clarify inter-specific relationships.