Earliest tinamous (Aves: Palaeognathae) from the Miocene of Argentina and their phylogenetic position.

BERTELLI, S.; CHIAPPE, L.M.

CONTRIBUTIONS IN SCIENCE (LOS ANGELES, CALIF.)

Natural History Museum of Los Angeles County

Lugar: Los Angeles; Año: 2005 vol. 502 p. 1 - 20

0459-8113

Several isolated bones of tinamous from Miocene deposits of Santa Cruz Province (southern Patagonia, Argentina) are the oldest known remains of this paleognath lineage. The specimens include an incomplete coracoid, proximal end of four coracoids, distal ends of two tibiotarsi, and distal ends of two humeri. They represent at least two species but cannot be assigned to any known taxon. A detailed description and phylogenetic interpretation of this material is provided here. Morphological data of the fossils are included in a matrix of 63 osteological characters and 34 terminal taxa incorporating 24 living species of Tinamidae in addition to the fossils under study. The cladistic analysis produced 81 optimal trees, in which the fossils are more closely related to the open-area tinamous (Nothurinae). Placement of the Santa Cruz fossil tinamous between the open-area (Nothurinae) and the forest-dwelling (‘‘Tinaminae’’) tinamous is consistent with the paleoenvironmental conditions inferred from the associated fossil fauna.