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Two new mammal localities have been discovered in the Lower Cretaceous Ilek Formation of West Siberia, Russia. The Smolenskii Yar locality in the Chebula District of Kemerovo Province produced an upper molariform tooth (M2) of a Gobiconodontidae indet. The Ust’-Kolba locality in the Tisul’ District of Kemerovo Province yielded a lower molar (m2) of the zhangheotherian Kiyatherium sp. These are the ninth and tenth Mesozoic mammal localities for Russia. The Kiyatherium -bearing vertebrate assemblage from the Shestakovo 3 and Ust’-Kolba localities is likely to be the youngest within the Ilek Formation, reflecting the time after the extinction of the Tritylodontidae. [ABSTRACT FROM AUTHOR]

Three new euharamiyidan taxa are described based on isolated teeth from the Middle Jurassic (Bathonian) Itat Formation of the Berezovsk coal mine in Krasnoyarsk Territory, Western Siberia, Russia. The newly erected Sharypovoia, gen. nov., is referred to the Shenshouidae based on a premolariform p4, in which the main cusp and basined heel are surrounded by two rows of cusps. Attributed upper molars have the main labial cusps A1 and A2 connected by a ridge that lacks small additional cusps. In the smaller species S. arimasporum, sp. nov., there are one to two additional cusps mesial to cusp A2, whereas the larger S. magna, sp. nov., lacks these additional cusps. Maiopatagium sibiricum, sp. nov. (Euharamiyida incertae sedis), is similar to M. furculiferum from the Late Jurassic Yanliao Biota of northeastern China in having coalesced crest-like lingual cusps and an open occlusal furrow medially on the upper cheek teeth. Sineleutherus uyguricus from the Upper Jurassic (Oxfordian) Qigu Formation in Xinjiang, China, is restricted to the holotype only, a lower molar, and referred to the Arboroharamiyidae. The previously published sample of 'Sineleutherus' issedonicus from the Itat Formation represents a mixture of shenshouid and arboroharamiyid euharamiyidan taxa, and the holotype of that species, a lower molar, should be referred to a new genus of Arboroharamiyidae. The Asiatic euharamiyidan taxa are referable either to Shenshouidae or Arboroharamiyidae, but not to Eleutherodontidae. [ABSTRACT FROM AUTHOR]

ABSTRACT—Anthracolestes sergeii, gen. et sp. nov., based on three isolated lower molars and several edentulous dentary fragments from the Middle Jurassic (Bathonian) Itat Formation at Berezovsk Quarry in Krasnoyarsk Territory, Russia, is the oldest and most basal representative of Dryolestidae. It shows four unambiguous synapomorphies of Dryolestidae: lower molars with unilaterally hypsodont crowns, unequal roots, and pronounced precingulid instead of cusp f, and dentary with unequal alveolar borders. The dental formula of the new taxon is i1–4, c (double-rooted), p1–4(?), and m1–4(?).Anthracolestes sergeii, gen. et sp. nov., is plesiomorphic relative to more derived and geologically younger dryolestids in having possibly fewer lower molars, less pronounced mesiodistal compression of lower molars, oblique protocristid, short mandibular symphysis, and shallow mandibular ramus of the dentary. Asia is most likely the place of origin for Dryolestidae, but this group is so far not known from that continent after the Middle Jurassic. SUPPLEMENTAL DATA—Supplemental materials are available for this article for free atwww.tandfonline.com/UJVP [ABSTRACT FROM AUTHOR]