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A new species of echinoderid kinorhynchs, Meristoderes okhotensis sp. nov. collected from oxidized brown silt at Kuril Basin, the deepest depression of the Sea of Okhotsk, northwestern Pacific, is described and illustrated using light and electron microscopy. This new representative of the most recently described genus Meristoderes from the family Echinoderidae is characterized by the structure of the second trunk segment consisting of an externally closed cuticular ring with indistinct intracuticular tergosternal junctions which are remarkably curved. This segment also bears pairs of subdorsal, laterodorsal and ventrolateral adhesive tubules. Trunk segment 5 with tubules in lateroventral position. Aciculate lateroventral spines on trunk segments 6–9. Meristoderes okhotensis sp. nov. is the only representative of the genus with two middorsal spines, on trunk segments 6 and 8. This species is well recognized by its exceptionally long tergal extensions of trunk segment 11, some of the longest within all kinorhynch species. Meristoderes okhotensis sp. nov. appears the deepest representative of the family Echinoderidae described so far. It constitutes the eighth species and the first deepwater representative of the genus Meristoderes. Also, this is the first species of kinorhynchs described from the Sea of Okhotsk. A key to the species of the genus Meristoderes is proposed.

According to recent reports, shell morphology is unreliable for the identification of oysters because of the high phenotypic plasticity of these bivalves. Using COI DNA barcoding and sperm morphology, we reinvestigated the species validity of wild Pacific oyster Crassostrea gigas habituating the Peter the Great Bay (Sea of Japan). DNA barcoding confirmed the species validity of samples collected. Application of the single sperm pattern was not possible for species identification due to pronounced sperm plasticity being found. Six sperm morphs were discovered in the testes of each oyster collected. The amount of abundant sperm morphs and the type of the most dominant sperm pattern are particular to geographical localities that are individual depending on the environmental factors. Ecological monitoring of marine areas and commercially assigned intraspecific geo-authentification of the Pacific oyster seems possible based on the analysis of this species’ heterogenic sperm. Further work will be needed to test if sperm heterogeneity exists in other Ostreidae species and if heterogenic sperms could be used for interspecific analysis.

Primitive monodromy groups of rational functions P/Q, where Q is a polynomial with no multiple roots and deg P > deg Q+1 are classified. There are 17 families of such functions which are not Belyi functions. Only one family from the list contains functions that have five critical values. All the remaining families consist of functions with at most four critical values and constitute one-dimensional strata in the Hurwitz space. The action of the braid group on generators of their monodromy groups is computed and the corresponding megamaps are drawn. The result extends the classification of primitive edge rotation groups of weighted trees obtained by the author and Zvonkin and is also a generalization of the classification of primitive monodromy groups of polynomials obtained by P. Muller.

Based on the available literature data, museum collections, and our own material, a review is presented on sipunculan species of the northwestern Pacific that occur at depths greater than 500 m. Brief morphological descriptions showing the main characters used in taxonomy and a key for the identification of deep-sea sipunculans of the northwestern Pacific to species level are proposed. The key includes 22 valid species representing 7 genera and 5 families of Sipuncula.

Hot pressing is used to prepare composite ceramic based on cubic boron nitride (CBN) reinforced with carbon nanostructures. Carbon nanostructures (CNS) are synthesized by hydrocarbon pyrolysis in a plasm-jet reactor in an argon plasma. The effect of composite material nanostructuring is obtained from results of study and specification of test composite specimens and starting materials by physicochemical methods, x-ray diffraction, and electron microscopy. This leads to a change in its functional properties.

A new species of centroderid kinorhynchs, Condyloderes kurilensis sp. nov., collected from muddy sediment at the abyssal plain near the Kuril-Kamchatka Trench, North-West Pacific, is described and illustrated using light and electron microscopy. Previously, members of the genus Condyloderes were found only in nearly shallow water enviroments—C. multispinosus (North Sea), C. paradoxus (Bengal Bay), C. setoensis (Tanabe Bay, Japan), C. storchi (Argentina coast), and C. megastigma (Korea Strait). The new species is characterized by the presence of lateroventral cuspidate spines only on trunk segment 8 in both sexes, paired ventromedial appendages (tubules) on trunk segments 7 and 8 in females only, and dorsolateral spines on trunk segment 10 in males only. Condyloderes kurilensis sp. nov. constitutes the sixth species of the genus Condyloderes described so far and the only second abyssal species of the Kinorhyncha described from the North-West Pacific. A key to the six species of the genus Condyloderes is proposed.

During KuramBio and KuramBioII (Kuril Kamchatka Biodiversity Studies) expeditions of 2012 and 2016 years, 12 sites across the Kuril-Kamchatka abyssal plain and 11 sites along Kuril-Kamchatka Trench area (KKT) were surveyed and sampled and benthic communities were investigated. Samples, which comprised over 300 echiurans from 12 species of 11 genera belonging to the family Bonelliidae and Thalassematidae, were collected. The family Bonelliidae is most common in abyssal and hadal environments in the world ocean with high abundances in all investigated regions, while Thalassematidae is reported first time from the hadal depth. Species identified as representative of the genera Maxmuelleria have been noted first time in Pacific. Previously known echiuran Bonellia pacifica suggested to be Pseudoikedella achaeta. The description of deep-water echiurans from the investigated areas is the second one based on complete specimens with living colouration. The descriptions provide new information on the distribution, abundance, morphology and taxonomic details of the species, which were previously noted from the northwestern Pacific and described from damaged or incomplete specimens. The knowledge of the geographic ranges of these genera are expanded and discussed.

Introverts of Priapulus caudatus and P. tuberculatospinosus bear 25 rows of scalids, as well as 8 spines and scattered papillae in the region the circumoral lip. These, as well as the first ring of pharyngeal teeth in P. tuberculatospinosus, are sensory organs. Although superficially they differ between species, they are all characterized by apical and/or subapical openings which are located on tiny cuticular tubules. All sensory organs contain cilia bearing bipolar receptor cells. The 8 sensory spines situated between the circumoral area and the beginning of the scalids are ultrastructurally similar to the scalids. The introvert and pharyngeal body walls, and associated muscles are described. © 1994 Wiley-Liss, Inc.

в работе отмечено, что в современных условиях при планировании застройки и развитии городских территории все большую значимость приобретают организационные и экологические факторы, оказывающие наибольше влияние на изменение уровня жизни населения. Инженерная и планировочная организация новых территорий должна быть наиболее комфортной и рациональной для населения: районы должны иметь связь с центральной частью города и другими его районами, расположение жилых домов должно обеспечивать оптимальные условия инсоляции и проветривания. Экологическая обстановка на территории жилых микрорайонов не должна оказывать вредного воздействия на людей и окружающую среду. Все это является основой в формировании экологического каркаса территории муниципального образования.

Deep-sea sipunculans collected during the expedition to the Kuril-Kamchatka Trench and adjacent abyssal plain are described and illustrated using differential interference contrast microscopy (DIC) and scanning electron microscopy (SEM). Specimens were sorted from brown silt collected by giant boxcorer (GKG), epibenthic sledge (EBS) and Agassiz trawl (AGT) from the depths 4830–5780 m. Within about 150 valid species of sipunculans only 15 have been known to be abyssal and six of them were found and identified in this KURAMBIO expedition. Eight species of sipunculans have been previously recorded from the Kuril-Kamchatka region but all of them were described based on preserved museum׳s material collected by bottom dredge and these descriptions are far from to be complete and comparable with other samplings. All KURAMBIO species are described according to a unified protocol to illustrate the most important taxonomic characters. This is the first description and illustrating of abyssal sipunculans in live condition with natural coloration of non-preserved specimens. Abyssal species were for a first time described with SEM facilities and according to a standardized protocol. For a first time for abyssal sipunculans, species accounts also include quantitative characteristics, distribution and specific biotope data. Nephasoma abyssorum is reported for the Kuril-Kamchatka Trench and adjacent abyssal plain for a first time.

A new homalorhagid kinorhynch, Pycnophyes abyssorum sp. nov., found in brown silt from the abyssal depth at the Kuril-Kamchatka Trench is described and illustrated using differential interference contrast (DIC) microscopy and scanning electron microscopy (SEM). This is the ninth species of the genus to be described from the North–West Pacific and the first representative of the Kinorhyncha described from the Kuril-Kamchatka Trench. P. abyssorum sp. nov. constitutes the 16th species of Pycnophyes known from the Pacific and 55th species of the genus described based on adult specimens. P. abyssorum sp. nov. is the only second abyssal species of kinorhynchs and the deepest one described so far. The species is characterized by a unique combination of characters. P. abyssorum sp. nov. is distinguished from other congeners by the presence of long and sharp middorsal processes on trunk segments 1–10; strongly denticulated anterior margin of first tergal plate with wide submarginal area of reticulate cuticle; single paradorsal seta on trunk segments 2–4 and 7–9(8–9); two pairs of lateroventral setae closely adjacent to tergal–sternal articulation on trunk segment 10; two pairs of flosculi-like sensory papillae and one pair of terminal tubular papillae on posteriormost tergal plate. Anteromesial thickenings of ventral pachycycli absent in both sexes.

The microscopic anatomy and ultrastructure of the contractile vessel of the sipunculan Themiste hexadactyla (Sato, 1930) from Vostok Bay (the Sea of Japan) were studied by histological and electron microscope methods. The ultrastructural features of the internal (endothelium) and external (coelothelium) lining of the contractile vessel are described and illustrated. Numerous macromolecular filters, the so-called “double diaphragms,” were found in the external coelothelium facing the cavity of the trunk coelom. This suggests a possible filtration from the tentacular coelom into the trunk coelom though the contractile vessel wall. The microscopic peculiarities of the main tube of the contractile vessel and its numerous lateral branches twining around several internal organs are described in detail. The contractile vessel is polyfunctional: it can act as the main reservoir for the cavity fluid during the withdrawal of the tentacular crown and performs the functions of the distribution system in sipunculans.

The microscopic anatomy and ultrastructure of the nephridia of the sipunculan Themiste hexadactyla (Sato, 1930) from the Sea of Japan were studied by the histological and electron microscopic methods. The fine structures of the ciliary funnel, muscular “tongue,” excretory sac, and excretory tube of the nephridium were described. The ultrastructural features of the excretory epithelium, cupola-shaped epithelial infoldings, excretory canals, and muscular layer in the extracellular matrix of the nephridial wall were examined and described in detail. The ultrastructure of the nephridial coelomic epithelium composed of podocytes with long processes and multiciliary cells was also examined and illustrated. Characteristic cell contacts between the processes of podocytes, viz., paired “double diaphragms,” were described and illustrated for the first time.