The most complete known Neogene Glyptodontidae (Mammalia, Xenarthra, Cingulata) from northern South America: taxonomic, paleobiogeographic, and phylogenetic implications

ABSTRACT

The knowledge of northern South American Glyptodontidae (Mammalia, Xenarthra, Cingulata) is very scarce compared with that of southern South American taxa, which have been systematically studied since the 19th century. Recently, the northern taxa (originally assigned to the Glyptodontidae Propalaehoplophorinae Asterostemma and Propalaehoplophorus) have been reinterpreted as basal Glyptodontinae, belonging to the new genus Boreostemma. In this contribution, we present and describe the most complete Neogene Glyptodontidae from northern South America (middle Miocene of the Honda Group, La Venta, Colombia), and its main taxonomic, paleobiogeographic, and phylogenetic implications. This new material expands the morphological characterization of B. acostae and corroborates differences compared with Glyptodontidae from Miocene southern South America. A cladistic analysis corroborates the monophyly of the Glyptodontinae, that B. acostae and B. venezolensis being the sister group of the remaining taxa of Glyptodontinae. The traditionally recognized genera (e.g., Glyptodon and Glyptotherium) constitute natural groups. Whereas the Miocene seems to represent a diversification period for Glyptodontidae in southern South America, the recorded taxa in northern South America are restricted with certainty only to the Glyptodontinae Boreostemma.

ACKNOWLEDGMENTS

We thank the staff at the Centro de Museos of the Universidad de Caldas, Manizales, Colombia; at the Instituto de Ciencias Naturales (ICN) and Departamento de Geociencias, Universidad Nacional de Colombia, Bogota D.C.; and Museo Geológico Nacional ‘José Royo y Gómez,’ Servicio Geológico Colombiano (formerly INGEOMINAS), Bogotá, D.C., for allowing us the study of the materials. G. Tobón found the fossil CAL-896. O. Guerra, J. O. López, V. Calderón, A. Murillo, A. Betancourth, and others contributed to the conservation of the fossil CAL-896. F. Gois provided us useful information on Pampatheriidae. Both reviewers (D. Perea and D. Gillette) are also thanked for their thorough reviews and helpful suggestions. Comparisons with specimens from the AMNH and YPM by L.R.G.R. were made possible thanks to the Collection Study Grant (AMNH, U.S.A.) and the Ernst Mayr Travel Grant in Animal Systematic (MCZ, U.S.A.). Willy Hennig Society allowed free access to TNT software. This work was funded by project grants PICTO-UNNE (2007-00164), PICT 1285/2008, PI002-11, and GEO09-08(2011)-[BPIN 0043000150000].

Handling editor: Thomas Martin.