Vol 53, No 5 (2019)

New radiolarian taxa are described from the Lower and Middle Famennian of the Polar Urals and Volga–Urals Basin: three new genera Natgorella gen. nov., Spinoalius gen. nov., Diversiacus gen. nov., and three new species N. elegans sp. nov., N. hirsuta sp. nov., and S. melekessensis sp. nov. New taxa belong to two orders, Entactiniata and Cancelliata, of two classes of spherical radiolarians: Sphaerellaria and Spumellaria. Morphotypes of the outer skeletons of Spinoalius gen. nov. and Diversiacus gen. nov are shown to be convergently similar. A new Middle Famennian Natgorella hirsuta–Spinoalius melekessensis radiolarian ecozone is established.

A new genus and species Termihabena lirata gen. et sp. nov. is described from the Lower Permian reef limestones of Shakh-Tau (southern Cisuralia). The new genus includes another five species: T. nikitowkensis (Yakowlew, 1899), T. asiatica (Licharew, 1967), T. millegranosa (Girty, 1934), T. pinegensis (Mazaev, 2006), and T. sp. (Batten, 1985). T. pinegensis is re-described based on new, additional material. The morphological similarities and differences between the new genus and Deseretospira Gordon and Yochelson, 1987 are discussed. The diagnosis of the genus Deseretospira is emended and expanded. Deseretospira and Termihabena gen. nov. are assigned to the family Phymatopleuridae. Deseretospira includes D. venustiformis (Licharew, 1967), in addition to the type species. The revision showed that the two species Rhineoderma ferganica Licharew, 1967 and Yunnania semigranulosa Licharew, 1967 are synonymous with Deseretospira venustiformis (Licharew, 1967).

The type species of the genus Praesurites,P. elegans Mesezhnikov et Alekseev, was described from the basal Berriasian of the Subpolar Urals (Sosva River basin). Finds of species of this genus in other regions are of importance for the interregional correlation of the Jurassic–Cretaceous boundary interval. The taxonomic composition and stratigraphic distribution of the Central Russian species of the genus Praesurites from the Volgian–Ryazanian boundary interval (the top of Craspedites nodiger Zone–Riasanites rjasanensis Zone) are revised. The revised diagnosis of the genus Praesurites and redescriptions of P. tryptychus (Nikitin), P. unshensis (Nikitin) (including P. nikitini Gerasimov et Mitta, as a junior subjective synonym) and P. craspeditoides (Girmounski) are presented.

A new poteriocrinid genus, Magnofossacrinus, represented by the type species M. domodedovoensis sp. nov. from the Upper Carboniferous deposits of the Moscow Synecline, is described. The new genus is the youngest (Moscovian stage) reliable representative of the family Poteriocrinidae. Magnofossacrinus is characterized by unusually large cirrus with polynodal articular facets. The morphology of Magnofossacrinus stems is discussed and compared with the stems of other closely related crinoids.

Three new species of caddisflies from Polycentropodidae, Phryganeidae and Leptoceridae: Plectrocnemia victori sp. nov., Wigginsiola saecularia gen. et sp. nov., Electrotriaenodes mosquensis sp. nov. are described from the Eocene Baltic amber.

An extinct species of tubesnouts belonging to the modern genus Aulichthys, A. miocaenicus sp. nov., was found in the deposits of the Serravalian–Tortonian of the Agnevo Formation of Sakhalin Island. This is the first reliable fossil record for the family Aulorhynchidae. The Miocene species is similar to the only modern relative in main proportions and morphological characters, but it differs in more developed bony structures such as large plates on the trunk, as well as in longer pelvic and anal spines. Another special feature of the Miocene species is well-developed ornamentation of the surface of trunk plates and ventral pelvic spine. The presence of tubesnouts in the fossil assemblage of Agnevo Formation indicates the shallow depth of the habitat of this community, as well as warmer climatic conditions in the Miocene at the latitude of Agnevo locality.

New species of osmundaceous ferns, Osmundastrum gvozdevae sp. nov., is established on the basis of small coalified stems with preserved cellular structure, originated from the Upper Bathonian deposits of the Mikhailovskii Rudnik locality (Kursk Region, European Russia). Vascular tissues of the stem are represented by ectophloic dictyoxylic siphonostele; pith homogenous, comprising prosenchymatous cells only. Xylem of the leaf trace is endarch, with protoxylem strand, bifurcating when passes through the external part of an outer cortex. Leaf bases with stipular wings; their vascular bundles are horseshoe-shaped, with two sclerenchyma masses on the side of adaxial concavity. Sclerenchyma rings in the leaf bases are heterogeneous, thick-walled fibers form distinct abaxial arch and two lateral masses. The new species is provisionally assigned to the extant genus Osmundastrum C. Presl on the basis of the stem anatomical peculiarities.