The skull of Tonatia bidens Spix, 1823, found in ancient deposits of Abismo Ponta de Flecha Cave, Ribeira Valley, Southeastern Brazil

Abstract

The Ribeira Valley, located in the southern part of Sao Paulo State, contains an extensive cave system where vertebrate fossils from the Late Pleistocene and Holocene have been found. The Abismo Ponta de Flecha Cave, a vertical cave rich in osteological material, is subdivided into lateral galleries known as Jazidas. Previous paleontological studies have described several extinct and extant species, but chiropterans were only briefly mentioned in the initial study of this cave, with only a single fragmented skull reported. This study presents that skull and briefly discusses the locality where it was found. The specimen belonged to an adult individual of Tonatia bidens, discovered in Jazida 6, an intermediate level located some distance from the cave entrance. Bat osteological remains are fragile and easily destroyed in high-energy environments; therefore, the preservation observed in this Jazida may indicate that the specimen died in situ, without being transported. Although this area experienced intense sediment remobilization in the past, Jazida 6 shows evidence of stability and minimal reworking activity, as indicated by the preservation of fragile specimens, sometimes still in their anatomical position at death.