N. V. Zelenkov

Diving Ducks from the Middle Miocene of Western Mongolia

Medium-sized diving ducks from the Middle Miocene of the Sharga locality (western Mongolia) are described. Sharganetta mongolica gen. et sp. nov. and Nogusunna conflictoides gen. et sp. nov. are evolutionary more advanced than the thoroughly studied Early Miocene genus Mionetta, but more primitive than Anatinae and Oxyurinae. The humeral morphology gives evidence of an aberrant position of the two new genera. Another taxon, Protomelanitta gracilis gen. et sp. nov. presumably belongs to basal Mergini.

Neogene phasianids (Aves: Phasianidae) of Central Asia: 1. Genus Tologuica gen. nov.

A new genus, Tologuica, with two species (T. aurorae sp. nov. and T. karhui sp. nov.), from the Middle Miocene of the Sharga locality (western Mongolia) is described. The new genus shares some characters with the extinct genera Palaeocryptonyx, Palaeortyx, and Plioperdix and with extant Coturnix. The foot structure suggests that Tologuica resembled in ecology the European genus Palaeortyx and was probably adapted to an arboreal mode of life, in contrast to the terrestrial Coturnix and Plioperdix.

A new duck from the Middle Miocene of Mongolia, with comments on Miocene evolution of ducks

A new relatively large duck, Chenoanas deserta gen. et sp. nov. from the Middle Miocene of the Sharga locality, which is morphologically intermediate between the extant genera Chenonetta and Tachyeres, is described. The diversity of Early and Middle Miocene ducks is discussed. It is noted that some Middle Miocene duck remains are incorrectly referred to the genus Mionetta. The distribution of morphological characters of the humerus in Neogene and extant ducks shows that the present day diversity of ducks apparently results from extinction of some taxa which were formed in the Oligocene-Early Miocene. The distribution of morphological characters in the evolution of diving ducks is evidence that not only the formation of different morphotypes but also so-called “evolutionary maturation” of taxa also explains the modern diversity.

Dabbling ducks (Aves: Anatidae) from the Middle Miocene of Mongolia

A new genus and two new species of ducks (Aves: Anatidae) from the Middle Miocene Sharga locality are described. Mioquerquedula minutissima gen. et sp. nov. is a very small duck. Anas velox Milne-Edwards, 1868 from the Middle Miocene of France is transferred to the genus Mioquerquedula. Aix praeclara sp. nov. described here is the oldest record of the modern genus Aix. A revision of the previously described small duck Anas soporata Kurochkin, 1976 shows that only the specimens from the Sharga locality should be referred to this species. The status of other small ducks from the Neogene of Europe and North America is discussed. The diversity of herbivorous and diving ducks in the Sharga locality indicates that Miocene Shargyn Govi Lake was rich in food resources.

Neogene phasianids (Aves: Phasianidae) of Central Asia: 2. Genera Perdix, Plioperdix, and Bantamyx

The phasianid genera Perdix, Plioperdix, and Bantamyx from the Neogene of Mongolia and Transbaikalia are reviewed. Based on published data and new material, the diagnoses of Late Pliocene Perdix margaritae Kurochkin and Plioperdix ponticus (Tugarinov) and Late Miocene Bantamyx georgicus Kurochkin are emended. It is shown that a tarsometatarsus from the Upper Miocene of the Pavlodar locality belongs to the genus Palaeoperdix rather than Palaeortyx, as was proposed in the previous studies. Small Neogene Asian phasianids are compared in detail with Neogene taxa from Europe and extant genera.

Evolution of bird communities in the Neogene of Central Asia, with a review of the Neogene fossil record of Asian birds

A complete taxonomic review of Neogene birds of continental Asia is provided. To date, avifauna from the latter half of the Miocene and Pliocene of Central Asia (Mongolia and adjacent regions of Inner Asia) are most thoroughly investigated. Available data enable a reconstruction of successive replacement of Early and Middle Miocene avifaunas by communities of the Recent type. Middle Miocene avifaunas of Mongolia include a great number of extinct genera and species, many of which were widespread in Eurasia. Extant genera became dominant in the Late Miocene and taxa close to living species appear in the Late Pliocene fossil record. Late Pliocene communities of birds of Central Asia were complex in genesis, composed of Miocene relicts (Struthio), immigrants from the European regions of the Palearctic (phasianid Plioperdix), North American immigrants (Calcarius), and also autochthonous elements, the origin of which is apparently connected with the arid belt of Central Asia (diverse passerines).

A primitive grebe (Aves, Podicipedidae) from the Miocene of Eastern Siberia (Lake Baikal, Olkhon Island)

A small grebe, Miobaptus huzhiricus sp. nov., is described from the uppermost Lower Miocene–lower Middle Miocene of Olkhon Island (Lake Baikal; Tagai locality). This fossil grebe differs from all extant representatives of the family in several morphological features, which indicate a stem position of the genus Miobaptus in the phylogenetic tree of Podicipediformes. This Asian record of the genus Miobaptus, which was initially described from the Lower Miocene of Central Europe, is evidence of wide distribution of at least some genera of water birds in the Burdigalian of Eurasia. A review of the Miocene and Pliocene fossil record of Podicipedidae is provided. The previously undescribed grebe from the Middle Miocene of the Steinheim locality in Germany is also referred to the genus Miobaptus, although it possesses more derived morphology compared to M. huzhiricus. The genus Miobaptus partially bridges the morphological gap between Podicipedidae and other avian taxa, for example, Palaelodidae. Early evolution of Podicipedidae is discussed.

Neogene geese and ducks (Aves: Anatidae) from localities of the Great Lakes Depression, western Mongolia

New material of ducks and geese from Late Miocene-Early Pliocene localities of the Great Lakes Depression in western Mongolia is described and the previously described material is revised. This study confirms the presence of four goose species, four dabbling ducks, and three diving ducks. A large goose previously described as Heterochen vicinus is assigned to a separate genus, Heteroanser. Bonibernicla ponderosa is transferred to Anserinae, and North American Branta woolfendeni is regarded as a junior synonym of Bonibernicla ponderosa. The validity of two goose species, Anser devjatkini and A. liskunae, is confirmed and both are assigned here to the subgenus Chen. It is also shown that the holotype of Anas molesta actually belongs to a diving duck of the genus Aythya. The presence of Anas soporata in the Hyargas Nuur Formation is not confirmed.

Ardea sytchevskayae sp. nov., a new heron species (Aves: Ardeidae) from the Middle Miocene of Mongolia

A new heron species, Ardea sytchevskayae sp. nov., from the Middle Miocene Sharga locality is described. The new species is represented by an almost complete coracoid and a few partial coracoids, partial scapula, and caprometacarpus. A. sytchevskayae was a relatively large heron, of the same size as A. alba, and intermediate in morphology between A. alba and other species traditionally included in this genus. In addition, the Sharga locality has yielded a large bittern and a medium-sized heron of uncertain taxonomic position.

Neogene phasianids (Aves: Phasianidae) of Central Asia: 3. Genera Lophogallus gen. nov. and Syrmaticus

Large phasianids from four Miocene and Pliocene localities of Mongolia are reviewed. Lophogallus naranbulakensis gen. et sp. nov. from the Middle Miocene of the Naran Bulak locality is described. It resembles extant Gallus, Lophura, and partially Pavo. The fossil pheasant Syrmaticus kozlovae Kurochkin is compared in detail with other Neogene and living pheasants. The stratigraphic position of phasianids from Neogene localities of Central Asia is discussed.