A stem bat (Chiroptera: Palaeochiropterygidae) from the late middle Eocene of northern Anatolia: implications for the dispersal and palaeobiology of early bats

摘要

Fragmentary remains of an Eocene bat are described from the middle Eocene Luluk Member of the Uzuncaridere Formation on the Pontide terrane, in what is now north-central Anatolia. The new taxon most closely resembles the palaeochiropterygids Lapichiropteryx and Stehlinia in terms of its known dental morphology, and it is referred to the stem chiropteran family Palaeochiropterygidae on this basis. Geological and palaeontological data indicate that the Pontide terrane was an island situated along the northern margin of Neotethys during the middle Eocene. The presence of a late-surviving stem chiropteran in an island context potentially illuminates dispersal patterns and capabilities among the earliest bats, which already enjoyed a nearly global distribution by the early Eocene. Other palaeochiropterygids for which postcranial material is known share little in common with extant bats that are capable of long-range dispersal across open water. The new Turkish bat taxon is consistent with a hypothetical dispersal corridor between Western Europe and India via islands on the northern margin of Neotethys and suggests a larger range of skeletal and locomotor variation within Palaeochiropterygidae than is currently recognised.