TAXONOMIC CLASSIFICATION OF FOSSIL REMAINS FROM CAVE DEPOSITS IN CIALES, PUERTO RICO

Fossil remains were extracted from an exposed cave deposit in Ciales, Puerto Rico. These deposits consist of seven stratigraphic interbedded units of siltstone and flowstone. A total of six vertebrate fossils and one invertebrate gastropod shell were studied. The shell belongs to the gastropoda, Caracolus marginella (Gmelin, 1791). The vertebrate samples are three mandibles, a left scapula, a partial skull and a right femur. The vertebrates were classified via comparative anatomy to genus or species. The dentition of the mandibles and the partial skull suggests two different species of rodents, Elasmodontomys obliquus Anthony (1916) and Heteropsomys insulans Anthony (1916). The right femur is possibly related to a bird species from the genus Tyto Billberg (1828); depicting a large owl associated to caves and common in the West Indies. Different species of vertebrates were preserved in scattered distribution and show no evidence of transportation. The presence of an owl femur among the fossils may suggest that the studied area was possibly a place where predatory birds would eat their prey and scatter the remains at the cave entrance. Radiocarbon dating was conducted using two disarticulated mandibles from Elasmodontomys obliquus but no age was obtained because these remains were permineralized.