Pliocene lagomorphs and rodents from Udunga, Transbaikalia, eastern Russia

Abstract

Hundreds of lagomorph and rodent fossils from the Middle Pliocene of Udunga are stored in the Southern Scientific Center, Russian Academy of the Sciences. They have been studied taxonomically. The lagomorph fossils include three forms of ochotonids such as Ochotona cf. gromovi, Ochotona sp. (large form) and Ochotonoides complicidens, and two forms of leporids such as Hypolagus sp. and Leporidae, gen. and sp. indet. The rodent fossils include one castorid species (Castor anderssoni), one siphneid form (Prosiphneus cf. praetingi) and one arvicolid form (Villanyia sp.). Among them, Castor anderssoni is highly predominant, and attains to more than 50 % of all the lagomorph and rodent specimens identifiable at the family, genus or species level. These fossils provide additional knowledge to the small mammal fauna of Udunga already reported.