Nº 3 (2023)

Systematic position and status of the genus Bathropyramis Haeckel, 1882, restituo et emend. Amon et Vishnevskaya, nov. (Radiolaria, order Nassellaria, family Plectopyramididae) are considered, evaluated and revised. The diagnosis of reinstated genus Bathropyramis is clarified, and descriptions of the most ancient species Bathropyramis filatovae Vishnevskaya, 2001, emend. Amon et Vishnevskaya, nov., from Callovian of the Koryak Highlands, and B. sanjoaquinensis Campbell et Clark, 1944, emend. Amon et Vishnevskaya, nov. from Upper Maastrichtian of the Koryak-Kamchatka region, Cinclopyramis victori (Lipman, 1960), emend. Amon et Vishnevskaya, nov., from Eocene of Kamchatka are given.

From the lower part of the Tommotian Stage of the Lower Cambrian of Western Mongolia, ridge Hevte-Tsakhir-Nuruu described a new species of problematical microfossils of the genus Aetholicopalla Conway Morris in Bengtson et al., 1990, whose representatives are sometimes the dominants of the Early Cambrian taphocoenoses. A. grandipora sp. nov. – spheroidal organisms with initially carbonate (?) skeleton; planktonic and benthic forms described; the latter have a variable shape and attachment sites to the bottom substrate. The outer wall of the fossils is perforated, thin, double; the functional implication of the holes is unclear; be present an internal cavity. By mode of existence, these organisms were probably filter feeders. Geochemical analysis of various taphomorphs showed that A. grandipora sp. nov. preserved by phosphate and siliceous mineralization in the early stages of fossilization. The set of recognized characters allows us to attribute Aetholicopalla to the first skeletal Porifera of an unclear taxonomic position; perhaps these were juvenile forms of organisms close to archaeocyates.

For the first time in the Lower Permian deposits (Upper Asselian–Sakmarian stages) of the Southern Cis-Urals, the most ancient representatives of oyster-like bivalves of the genus Prospondylus Zimmermann were found, reliable findings of which were previously known only in the Lower-Middle Permian deposits of North America and the Upper Permian deposits of Germany. A description of the new species Prospondylus shakhtauensis Biakov, sp. nov. is given.

A review of the family Hydrobiidae from the Tarkhanian and Chokrakian deposits was made. New genus Islamiella was described, in which the species I. miocenica sp. nov. (upper Tarkhanian–lower Chokrakian) and I. maeotica sp. nov. (lower Maeotian) were included. Last species is widely distributed in the facies, concomitant with the bryozoan buildings of the Maeotian beginning. Peringia tarkhanica sp. nov. was described fom the Tarkhanian, whereas Hydrobia kubanica Zhizhchenko, 1936 was redescribed from the Chokrakian. Several species descibed earlier as Hydrobia by Zhizhchenko were synonymized with the species from the other families: H. subprotracta Zhizhchenko, 1936 icluded in synonymy of Finella andrusovi andrusovi (Bajarunas, 1910), and H. stavropoliana Zhizhchenko, 1936 reffered to the genus Odostomia, most probably to species O. nuda Bajarunas, 1910.

New representative of family Mesorthopteridae (Insecta; Eoblattida), Mesoidelia rasnitsyni sp. nov., from the Madygen locality (Middle or Upper Triassic of Kyrgyzstan) is described. Changes in composition of the family Mesorthopteridae in the Permian and Triassic are discussed.

A new species of the genus Acicnemis Fairmaire, 1849 is described from the early Miocene Sumatran amber. The new species, Acicnemis sumatranus sp. nov., differs from A. suturalis Roelofs, 1875 in the larger body size, a small antennal club, longer femora, and a large teeth on the metafemora. This is the first record of the tribe Acicnemidini in the Neogene and the first described beetle from Sumatran amber.

Five morphotypes of fossil burrows are described from four Eopleistocene paleosols from Sopaty Kurgan (Krasnodar krai, Russia). The architecture, ornamentation and diameter of fossil burrows was compared with a reference collection of modern burrows. The first morphotype is identified as Nannospalax sp. from its architecture, in particular, the shape of the lower junction of vertical shafts and tunnel diameter. The architecture (subhorizontal tunnels, absence of vertical ones), diameter and ornamentation of the second morphotype show affinities with the burrows of the modern water-vole, Arvicola terrestris; it possibly belongs to a large Mimomys sp. The third morphotype is identified as belonging to a large jerboa Allactaga sp. from the shape of the cross-section and diameter. The fourth morphotype is identified as a medium-large-sized arvicolid. The fifth morphotype is identified from the presence of spiral vertical tunnels as belonging to a mole-vole, Ellobius sp.