The first fossil barbet (Aves, Ramphastidae) from Siberia

Barbets are arboreal birds, inhabiting mainly tropical forests west of the Wallace’s Line. Fossil remains of barbets are extremely scarce. Until recently, only two species of barbets were described from the early and middle Miocene of Europe and several other undescribed fragments were mentioned in the literature. Here I report the first finds of barbets from Eastern Siberia. ?Capitonides sp. is here described from the late early Miocene of Baikal Lake based on a distal part of the humerus, an omal part of the coracoid, and a distal part of the ulna. The morphology of the fossil specimen does not allow attributing it to any of the modern genera, and thus ?Capitonides sp. is apparently a stem representative of the group. This find documents a previously unrecognized broad geographical distribution of barbets during the warmest phase (climatic optimum) of the Miocene. The observed similarity between the early–middle Miocene arboreal avifaunas of Western Europe and Eastern Siberia suggests the presence of a wide belt of relatively humid forests connecting Europe and Asia.