New finds and revised taxa of Early Pliocene birds from Western Mongolia

The Late Miocene-Early Pliocene Hyargas-Nuur formation in Western Mongolia yielded a rich fauna of birds which contributes significantly to our knowledge of the Neogene avian diversity in Asia. A study of new fossil remains, collected during the last 20 years, and a revision of several previously described taxa are presented in this paper. Cygnus pristinus is shown to be clearly separable from extant C. olor. Podiceps solidus and Haliaeetus fortis, initially described from the Late Miocene sediments, were found in the Early Pliocene. Probalearica mongolica is moved to the genus Grus, and a new genus Pastushkinia nov. gen. is erected for Crex zazhigini. Several new finds – a lapwing Vanellus cf. V. leucurus, two species of gulls (Larus spp.), and large Gypaetus-like accipitrid – represent the oldest records of the corresponding bird groups in Asia. A complete list of taxa known from the Early Pliocene of Western Mongolia is also presented.