Vol 52, No 12 (2018)

An assemblage of Late Precambrian macrofossils consisting of five species (Aspidella terranovica, Beltanelliformis brunsae, Nenoxites curvus, Palaeopascichnus renarius, and Suvorovella aldanica), was discovered in the type sections of the Yudoma Group of the Siberian Platform. A unique feature of the assemblage is the presence of carbonate discoidal remains of Suvorovella, formed as a result of secondary incrustation of basal structures, similar to Aspidella. The accumulations of redeposited fragments of Suvorovella formed the rock resembling the Phanerozoic shell beds. Except for this taxon, all members of the Yudoma assemblage have a wide geographic distribution. Their stratigraphic distribution tends to occur in the youngest deposits of the Upper Vendian, directly underlying the beds with small shelly fauna (SSF) of the Nemakit-Daldynian Stage, Cloudina tubes, and traces of the Treptichnus pedum Zone.

The genus Pluristratoentactinia Nazarov in Nazarov et al., 1981 is revised. The genus Pluristratoentactinia is shown to comprise 20 Early Devonian–Late Permian radiolarian species. Three new species of Early Permian radiolarians from the Southern Urals and Northern Mugodzhary are described: Pluristratoentactinia kondurovkensis sp. nov., P. kozuri sp. nov., and P. lusikae sp. nov.

Five new stonefly species from the Middle Permian Kostovaty locality in Udmurtia, Palaeonemoura benevola Sinitshenkova, sp. nov., Palaeotaeniopteryx trinerva Sinitshenkova, sp. nov., P. alligata Sinitshenkova, sp. nov., Palaeonemourisca corrugata Sinitshenkova, sp. nov., and Votaknemoura persuasibil Sinitshenkova, sp. nov. are described and assigned to the family Palaeonemouridae. The unique wing venation of Votaknemoura is briefly discussed.

New records of Saucrosmylidae from two Mongolian localities of Bakhar (upper Middle Jurassic–lower Upper Jurassic) and Khoutiin-Khotgor (Upper Jurassic) are reported. This is the first record of the family from Central Asia and the second finding outside the type locality of Daohugou (China). Two new species and a new genus, Chorilingia bakharica sp. nov. (Grammolingiidae) and Opapanfilovia bonata gen. et sp. nov. (Panfiloviidae) from Bakhar and Sai-Sagul (Kyrgyzstan, upper Lower Jurassic–lower Middle Jurassic) localities, respectively, are described. The complete list of known records of Grammolingiidae, Saucrosmylidae, and Panfiloviidae is provided. The clade Grammomorpha nom. nov. is introduced for the three families based on their venation characters. The analysis of the fossil record has shown that Grammomorpha was an exclusively Jurassic group that became extinct close to the Jurassic–Cretaceous boundary due to unknown causes.

Burrows of lungfishes are found for the first time in the Lower and Middle Triassic deposits of the Southern Cis-Urals. A preliminary description of these burrows and comparison with burrows of freshwater crustaceans are provided. Newly obtained paleoichnological data expand our knowledge of Triassic continental communities and abiotic conditions in Eastern Europe.

Cranial morphology of the type species of the genus Enosuchus, E. breviceps Konzhukova, 1955, is reexamined in detail based on the holotype and previously undescribed specimens from the type locality (Isheevo; Tatarstan, Russia; uppermost Urzhumian). E. breviceps is distinguished from known anthracosauromorphs by the intense osteogenesis of the dermal and endocranial bones, well developed surface ornamentation, the absence of the intertemporal, expanded interorbital region, and very massive quadrate.

A new lizard, Tsagansaurus nemegetensis gen. et sp. nov., from the Late Paleocene of southern Mongolia is described. It is assigned to the extinct family Parasaniwidae (Platynota, Anguimorpha). The new taxon is the latest representative of this group in the fossil record.

Morphological features of the membranous labyrinth in extinct and extant baleen whales and their ancestors are discussed. The tomography of the membranous labyrinth of two species of Late Miocene baleen whales from Adygea has shown that Kurdalagonus, Zygiocetus, and Cetotherium have a comparable number of cochlear turns with representatives of herpetocetins, i.e., about three turns. Representatives of the genus Kurdalagonus differ from Zygiocetus in the structure of semicircular canals, the longer crus commune (much shorter in Zygiocetus), and in the size of the ampulla of the lateral semicircular canal. In addition, representatives of the genus Kurdalagonus differ from Zygiocetus and Cetotherium in the structure of the round window, which is much wider and has a more rounded shape.

Based on the taxonomic composition of taphocoenoses of the main Paleolithic sites of the Anui River Basin within the northwestern Altai Mountains, the structure of mammal communities and potential composition of bioresources of the prehistoric man are reconstructed. It is shown that the basis of communities was composed of medium- and large-sized ungulates, including the Siberian ibex, argali, bison, and horses. A constant and important component of communities was the woolly rhinoceros. The following antelopes are regularly recorded in the Anui Basin: dzeren (Mongolian gazelle) and saiga. Roe deer and Asiatic red deer dwelt everywhere. The Asiatic red deer played a twice greater role than the roe deer as prey of humans. The major elements of communities and main competitors of humans were large carnivores, hyena and wolf. The main competitors in using caves were bear and hyena.

Traces of damage on fossil Taxodium leaves from the Tsagayan Formation of the Arkhara-Boguchan brown coal field (Amur Region, Russia; Paleocene) are studied using a scanning electron microscope (SEM). It is shown that the damage was caused by endophytic micromycetes. The problems of classification of microscopic damage to fossil plants are discussed.