New specimens of the earliest European passeriform bird

We describe new specimens of the oldest European passeriform bird from the early Oligocene of Germany. This bird has hitherto been known only from a poorly preserved skeleton and we report here a second slab of the same specimen and an additional fragmentary skull. The new specimens allow the description of a new species, Wieslochia weissi gen. et. sp. nov., which lacks apomorphies of crown group Oscines, the taxon including most extant and all European passeriform species. In overall osteology, Wieslochia most closely resembles extant Suboscines but these similarities may be plesiomorphic for Passeriformes. W. weissi differs from the stem species pattern hypothesized for Eupasseres in the morphology of the distal carpometacarpus, the absence of a hooked processus acrocoracoideus (coracoid), and the presence of furrows instead of certain canals on the hypotarsus, and may even be outside crown group Eupasseres, the clade including Oscines and Suboscines. Because the earliest European fossil record of oscine passerines is from the late Oligocene, passerines outside crown group Oscines may have colonized Europe before the arrival of Oscines from the Australian continental plate.