Rodents of the middle Eocene Shinzhaly fauna of Eastern Kazakstan

The Cricetidae (Rodentia, Mammalia) from the Ulantatal area (Inner Mongolia, China): New data concerning the evolution of Asian cricetids during the Oligocene

“…The absence of both species in UTL6 is coincident with the appearance of Tachyoryctoidinae. Such cases of interspecific competition are proposed in the Valley of Lakes and Kazakhstan (Emry et al, 1998;Lopatin, 2004;Daxner-Höck et al, 2010), except that tachyoryctoidines appeared as soon as the early Late Oligocene when C. dormitor was no longer present. The Ulantatal faunas are thus comparable to those of Kazakhstan, Mongolia (Lopatin, 1996;Daxner-Höck et al, 2010), and other Chinese faunas (e.g., Wang, 1987).…”

“…These extinct taxa therefore represent stem muroids rather than cricetids sensu stricto (Emry, 2007;Gomes Rodrigues et al, 2010); nevertheless this terminology is retained here for practical reasons. The oldest cricetids described, Palasiomys Tong (1997), and Pappocricetodon Tong (1992), are known from middle Eocene sites from China and Kazakhstan (Tong, 1992(Tong, , 1997Wang and Dawson, 1994;Emry et al, 1998). These early occurrences in Central and Eastern Asia emphasize the prominent role of this continent regarding the evolutionary history and historical biogeography of this group during the Paleogene.…”

Dental microwear in relation to changes in the direction of mastication during the evolution of Myodonta (Rodentia, Mammalia)

“…The oldest known Muroidea and Dipodoidea are from the Middle to Late Eocene of Asia (Dawson and Tong 1998;Emry et al 1998;Wang and Dawson 1994). The common ancestor of these two superfamilies must have had bunodont molars, quadrangular lower molars and square upper molars (Marivaux et al 2004).…”

New Stratigraphic Data from the Erlian Basin: Implications for the Division, Correlation, and Definition of Paleogene Lithological Units In Nei Mongol (Inner Mongolia)

“…In addition to a diverse group of ctenodactyloid rodents, at least two new miniscule rodents have been recognized from the Litolophus assemblage (unpublished data). One of them is a myodont that is morphologically more primitive than Elymys complexus from the early Middle Eocene (early Bridgerian) North American (Emry and Korth, 1989) and Middle Eocene Asian myodonts such as Aksyiromys dabs (Shevyreva, 1984;Emry et al, 1998), Primisminthus, and Banyuesminthus (Tong, 1997). The other represents a group unknown previously, which is similar to alagomyids in several dental aspects but has upper cheek teeth being considerably narrower (Meng et al, in press).…”