Vol 51, No 2 (2017)

The trend of species diversity and spatiotemporal distribution of spherical radiolarians of the genus Entactinia Foreman, 1963 in the Permian Period is analyzed. The center of origin of Permian entactinians in the Cis-Ural Paleobasin is established in the area of the modern interfluve of the Ural River and latitudinal current of the Belaya River on the Southern Urals. It is shown that the species composition of this genus almost completely changed in certain Permian epochs. Two forefather species of each new pleiad of Early, Middle, and Late Permian are revealed: Entactinia parapycnoclada and E. tyrrelli. Two new species of the Lower Permian radiolarians from the Southern Urals and Northern Mugodzhary, E. chernykhi sp. nov. and E. subquadrata sp. nov., are described.

Ammonites of the genus Spiroceras are described from the Upper Bajocian of the Kyafar River Basin (Karachay-Cherkessia), including macroconchs with preserved apertures and (for the first time in the entire history of the study of Middle Jurassic heteromorphs) microconchs with lateral lappets. The microconchs of S. bispinatum (Baugier et Sauzé), mainly represented by cyrtocones with one ventral row of nodes, correspond to microconchs with a gyroconic shell and a single row of nodes. Macroconchs and microconchs of S. annulatum (Deshayes), the ribs of which lack prominent nodes or spines, are found together. The assemblage also contains small-sized slightly uncoiled shells of Spiroceras aff. S. fourneti Roman et Pétouraud with widely spaced ribs and two prominent rows of large nodes, presumably macro- and microconchs. The ornamentation of this species resembles that of the monomorph Bajocia rarinoda Sturani from the upper part of the Lower Bajocian; perhaps the latter was ancestral to the Middle Jurassic heteromorph. The above species of Spiroceras, as well as S. obliquecostatum (Quenstedt), are figured.

The organophosphatic brachiopods of the superfamily Discinoidea, family Discinidae are described from the Upper Jurassic of West Siberia. The protegulum (embryonic shell) preserved in adult shells is for the first time discovered in Mesozoic discinids. The shell microstructure is studied. A new species, Discinisca undata Smirnova, sp. nov., is established.

The tracheal system of Saurophthiridae is described based on female fossils of Saurophthirus longipes Ponomarenko, 1976. Three very wide tracheal trunks are found running dorsolaterally along each side of the body. The tracheal system is amphipneustic, with the large mesothoracic and very large 8th abdominal spiracles. The 9th and following segments are able to turn back to open posterior spiracles for breathing. Taken together, these features are characteristic of air breathing aquatic insects. This urges us to modify the former hypothesis about parasitism of Saurophthirus on pterosaur wing membrane. We suppose that Saurophthirus females had gonotrophic cycles: they imbibed blood enough for maturation of a large egg batch, then retreated to a water body as a safe place for digesting and egg maturation, and after oviposition climbed onto emergent plants and waited for pterosaurs patrolling over the water and looking for fish, to start a new cycle. The families Saurophthiridae, Pseudopulicidae, and Tarwiniidae are united in the superfamily Saurophthiroidea Ponomarenko, 1986, stat. nov.

A new digger wasp, Florimena impressa gen. et sp. nov. (Hymenoptera: Crabronidae, Pemphredoninae), from the Upper Eocene shales of Florissant (Colorado, United States) is described. It is distinguished from all known members of the subtribe Spilomenina by the convex frons and in regularly rounded propodeum without a distinct bend between the upper and posterior sides.

Two new species of the subfamily Cossoninae are described from Madagascar copal. Pentarthrum inclusus sp. nov. is similar to P. alpinum Hustache, 1933 but differs in the smaller body size, almost straight rostrum, almost flat eyes, temples with smooth punctures, and the shorter 3rd antennomere. Cossonus shevnini sp. nov. is similar to C. suturalis Boheman, 1838, differing in the unicolorous body, uniformly punctured pronotum, and more convex eyes.

The position of dinocysts of the genera Scriniodinium, Endoscrinium, and Athigmatocysta in the family Gonyaulacaceae is discussed. It is shown that they were originally regarded as close morphotypes and changes in their taxonomy were associated with the evolution of views on some morphological features of the dinoflagellate shell as criteria for taxa of medium and high rank. It is proposed that the new subdivision is inconclusive, somewhat unnature, since it is based on the contentious details of tabulation. Morphological similarity of these dinocysts is indicated in the revised diagnosis of the genus Scriniodinium. The new cavate gonyaulacoid dinocyst species Scriniodinium multistratum sp. nov. from the Upper Volgian and Berriasian of the Nordvik section, northern Siberia, is described.