The Oldest Swallow (Aves: Passeriformes: Hirundinidae) from the Upper Lower Miocene of Southeastern Siberia

A new genus and species of fossil swallows, Miochelidon eschata gen. et sp. nov., are described from the Lower Miocene of the Baikal region. This is the only Miocene representative of Hirundinidae and the oldest fossil record of the group. The coracoid of Miochelidon combines generalized and specialized features, suggesting a basal position in the family for the genus. The ulna has a more advanced morphology, like in modern swallows. The find indicates a widespread distribution of basal swallows in the Early Miocene.