Ángel R. Miño-Boilini

A review of the Quaternary Tayassuidae (Mammalia, Artiodactyla) from the Tarija Valley, Bolivia

Three genera of Tayassuidae are recognized in South America: Platygonus Le Conte, 1848, Catagonus Ameghino, 1904 and Tayassu Fischer, 1814. This study provides the first systematic review of the Pleistocene tayassuids yet reported from Bolivia. The richest records of the family in South America derived from central-eastern Argentina and southern Brazil. Catagonus stenocephalus (Lund in Reinhardt, 1880) is documented for the first time in Bolivia, significantly extending the geographic distribution of this species in South America. We cannot confirm the validity of Platygonus tarijensis (Ameghino, 1904), but accept its generic allocation. Both taxa show adaptations to arid or semi-arid and relatively open environments, which is consistent with the palaeoenvironmental conditions previously proposed for the Tarija Valley. The veracity of other records of the family from Bolivia cannot be confirmed.

First record of Scelidodon chiliense (LYDEKKER) (Phyllophaga, Scelidotheriinae) from the Lujanian Stage (Late Pleistocene - Early Holocene) of Argentina

Fil: Mino Boilini, Angel Ramon. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Nordeste. Centro de Ecologia Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecologia Aplicada del Litoral; Argentina

Primer registro de Synbranchiformes (Teleostei) para el Holoceno temprano de Argentina

First record of Symbranchiformes (Teleostei) from the early Holocene of Argentina. In this contribution we present and describe the remains of the bony fish cf. Synbranchus, exhumed from fossiliferous levels of the Rio Bermejo Formation, Mansilla, southeastern Formosa province, Argentina. These materials constitute the only fish remains exhumed in this area, and they were found in association with extinct mammals which are characteristic of the Late Pleistocene and Early Holocene. Until now, only few fossil remains of Synbranchidae were known in South America. The earliest records come from the lowermost section of the Upper Pleistocene (“Belgranense”) from the Pampean region, Buenos Aires, Argentina. The materials coming from the Rio Bermejo Formation represent the first fossil record of a Synbranchidae cf. Synbranchus from the Early Holocene.

A review of the Quaternary Scelidotheriinae (Mammalia, Xenarthra, Tardigrada) from the Tarija-Padcaya basin, Bolivia

The Mylodontidae Scelidotheriinae (Mammalia, Xenarthra, Tardigrada) are a diversified clade of South American fossil ground sloths, with a wide geographic distribution, especially in high and middle latitudes. According to the last revision, the Quaternary diversity includes the genera Scelidotherium, Catonyx, and Valgipes. The clade Scelidotheriinae is well represented in the Pleistocene of the Tarija-Padcaya basin, and the first mention of these ground sloths correspond to the middle of the XIX Century. Since then, several species (i.e., Scelidotherium tarijensis, Scelidodon tarijensis, Scelidotherium capellini) have been reported as inhabiting the Tarija-Padcaya basin during the Pleistocene. Despite the abundance of fossil records of Scelidotheriinae in this area, no modern taxonomic revisions are available. In consequence, in this contribution a revision of the remains assigned to Scelidotheriinae from the Tarija-Padcaya basin is accomplished, and some biostratigraphic and geographic implications are discussed. Our results show that one single species (Catonyx tarijensis) can be recognized in the studied area, whereas a supposed smaller one (Scelidotherium patrium) actually corresponds to juvenile specimens of C. tarijensis.

Dimorphism in Quaternary Scelidotheriinae (Mammalia, Xenarthra, Phyllophaga)

Fil: Mino Boilini, Angel Ramon. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Nordeste. Centro de Ecologia Aplicada del Litoral. Universidad Nacional del Nordeste. Centro de Ecologia Aplicada del Litoral; Argentina

A Taxonomic and Biogeographic Review of the Fossil Tapirs from Bolivia

Fossil remains of South American tapirs are often fragmentary and scarce compared with those of other mammals that entered South America during the “Great American Biotic Interchange”. Here, we review and add to the Pleistocene tapir remains from the Tarija Valley (Bolivia), and provide a taxonomic re-evaluation of Tapirus tarijensis. T. tarijensis was a large-sized animal, approximating the size of the living Malaysian T. indicus and the extinct North American T. haysii. The geographical distribution of Pleistocene records of Tapirus in South America indicates that T. tarijensis was the only known species inhabiting the Tarija Valley during this time.