Pleistocene Bats (Late Irvingtonian and Late Rancholabrean) from Nuckolls and Sherman Counties, Nebraska

Abstract

We documented rare finds of fossil bats from two localities representing the Pleistocene epoch in southern and central Nebraska, Albert Ahrens locality (No-104, late Irvingtonian age, Middle Pleistocene), Nuckolls County, and Litchfield (Sm-102, late Rancholabrean age, latest Pleistocene), Sherman County. The Albert Ahrens local fauna with strong boreal influence yielded two bats, Lasiurus cf. borealis and Cf. Myotis sp. The Litchfield local fauna, also with a strong boreal influence, yielded two bats, Eptesicus fuscus and Cf. Myotis, among a diverse Pleistocene fauna of small vertebrates and pollen record indicating a boreal mixed conifer and deciduous woodland that contrasts with mixed grass prairies of the area in historic times prior to anthropogenic conversion. Vertebrate fauna from the Litchfield site can be assigned to the Rancholabrean land mammal age based on the presence of Bison, on faunal correlation, and on several extralimital taxa of small mammals. The fossil bat taxa are widespread in North America and still extant in Nebraska today; their glacial stage occurrences in a nonkarstic (caveless) region is consistent with previous interpretations of the Albert Ahrens and Litchfield local faunas as indicating cool equable climates and wooded parkland environments. These are the first bats to be reported from each of the respective paleofaunas.