Published online by Cambridge University Press: 08 February 2010
A fragmentary bone from the Dinosaur Park Formation (Campanian) of Dinosaur Provincial Park (Alberta, Canada), originally described as a pterosaur tibiotarsus, is reinterpreted as the distal end of the tibiotarsus of a basal bird, probably an enantiornithine, on the basis of several distinctive characters. It is the first report of such a bird from the Dinosaur Park Formation and shows that this group was present, together with various more derived ornithurines, in the relatively high-latitude environments of Late Cretaceous western Canada.