Growth variability in the late Vendian problematics <Emphasis Type="Italic">Parvancorina</Emphasis> Glaessner

Morphological and quantitative characteristics of the growth variability of two Parvancorina species were analyzed based on new abundant material from the Vendian of the White Sea. Growth variability in this problematic taxon appears to be wider than previously suggested. We found allometric growth in the White Sea population of P. minchami Glaessner, 1958, in contrast to isometric growth in Australian representatives of the species. Another White Sea species, P. sagitta Ivantsov, 2004, shows gradual formation of anchor-shaped structure in juveniles. Based on Australian material, it was previously believed that this structure did not change during ontogeny. These two distinctive features together with a strong variability of age-related measurements distinguish Parvancorina from other early arthropods (Scania, Primicaris), and cast doubt on the growth pattern as an argument in favor of the arthropodan nature of Parvancorina.     

Mitochondrial DNA divergence and phylogenetic relationships in mullets (Pisces: Mugilidae) of the Sea of Japan and the Sea of Azov revealed by PCR-RFLP-analysis

Three Mugilid species: Mugil cephalus (Linnaeus, 1758) and Liza haematocheila (Temminck et Schlegel, 1845; syn. Mugil soiuy, M. haematocheilus, L. soiuy, Chelon haematocheilus) from the Sea of Japan, as well as M. cephalus and Liza aurata (Risso, 1810) from the Sea of Azov were investigated on the basis of PCR-RFLP analysis of mitochondrial DNA (mtDNA) fragments, which included 12S/16S rRNA, and ND3/ND4L/ND4 genes. Among 61 individuals of three Mugilid species thirteen different haplotypes were detected. Eight and thirteen restriction endonucleases were found to be species-specific in 12S/16SrRNA and ND3/ND4L/ND4 respectively. This method may be useful for species identification. M. cephalus showed the largest genetic divergence while L. haematocheila and L. aurata were closely related and clustered together. The level of mtDNA differentiation between the two M. cephalus samples from the Sea of Japan and the Sea of Azov, i.e., nucleotide substitutions of approximately 3%, appeared to be relatively high.     

<Emphasis Type="Italic">Paralepidapedon variabile</Emphasis> sp. n. (Trematoda,Lepocreadioidea, Lepidapedidae) and other representatives of the genus <Emphasis Type="Italic">Paralepidapedon</Emphasis> from Antarctic fish

In the Ross Sea and Amundsen Sea, four representatives of the genus Paralepidapedon—Paralepidapedon cf. dubium Prudhoe et Bray 1973 sensu Sokolov et Gordeev 2013, P. lepidum (Gaevskaya et Rodyuk 1988), Paralepidapedon sp., and P. variabile sp. n.—were found in demersal fishes Muraenolepis marmorata and Macrourus whitsoni. Paralepidapedon variabile sp. n. is described from Muraenolepis marmorata in the Amundsen Sea. Paralepidapedon variabile sp. n. differs from other species of the genus Paralepidapedon by the position of the anterior border of the vitellarium at the level of the anterior edge of the ventral sucker or genital pore and by the highly variable shape of the testes: from roundish with a smooth edge to sinuate–lobate. Paralepidapedon lepidum was found for the first time in the Antarctic.     

The species composition and ecological features of pea crabs of the genus <Emphasis Type="Italic">Pinnixa</Emphasis> White, 1846 (Brachyura: Pinnotheridae) in Peter the Great Bay,the Sea of Japan

This paper provides an overview of pea crabs of the genus Pinnixa White, 1846 (Brachyura: Pinnotheridae) that occur along the Russian coast of the Sea of Japan. Three species of the genus have been recorded for this area: P. tumida Stimpson, 1858, P. rathbuni Sakai, 1934, as well as P. banzu Komai, Nishi & Taru, 2014, which is the first record for the fauna of Russia. All species clearly differ ecologically: P. tumida was found in Posyet Bay in the intestine of the burrowing holothurian Paracaudina chilensis (Müller, 1850); P. rathbuni, in burrows of the echiuroid Urechis unicinctus (von Drasche, 1881); and P. banzu, in tubes of the polychaete Chaetopterus cautus Marenzeller, 1879. The paper also provides a definitive key to Pinnixa species and data on the size, behavior, symbionts, and parasites of P. rathbuni and P. banzu.     

Summer Ichthyoplankon in Onega Bay of the White Sea: Species Composition and Spatial Distribution

Data on the species composition and distribution of ichthyoplankton in Onega Bay of the White Sea are presented for June–July 2007, 2010–2012, and 2015–2016. In the ichthyoplankton, the specimens of the early developmental stages of 21 fish species were registered; the larvae of the White Sea herring Clupea pallasi marisalbi, capelin Mallotus villosus, and Pacific sand lance Ammodytes hexapterus were the most abundant. It is shown that the northwestern and southeastern zones, distinguished in Onega Bay by hydrophysical parameters, also differ in species composition and in ichthyoplankton abundance.     

Mitochondrial DNA polymorphism of atlantic cod of the Barents and White seas

High level of intraspecific polymorphism of the mtDNA cytochrome b gene in the Atlantic cod Gadus morhua L. from the northeastern part of the species range (Barents and White seas) is detected. The absence of genetic differentiation between the samples from different areas of the Norwegian and Barents seas is shown, and the fact that these samples belong to the same population of Northeast Arctic cod is confirmed. Significant differences in the frequences of mitochondrial DNA haplotypes between the cod from the Barents and White seas, as well as from the northwestern part of the range, are found. The cod Gadus morhua kildinensis Derjugin, 1920 from Mogilnoye Lake and Gadus morhua marisalbi Derjugin, 1920 from the White Sea were revealed to have common haplotypes with the cod from the Barents Sea, confirming the recent origin of these forms from the Atlantic cod G. morhua.     

New and rare snailfishes (Liparidae,Scorpaeniformes) with the description of four new species from the Southern Hemisphere and tropical east Pacific

New and rare liparid fishes (Liparidae, Scorpaeniformes) are found and described. Careproctus armatus Andriashev, 1991 sampled off the South Sandwich Islands (at a depth 2281–2369 m); it is the second record of the species. Four species are collected in the vicinity of the South Shetland Islands: Careproctus parini Andriashev et Prirodina, 1990 (off King George Island, 573–861 m), Paraliparis meganchus Andriashev, 1982 (off Elephant Island, 559 m), P. monoporus Andriashev et Neyelov, 1979 (off Elephant Island, 559 m) and Paraliparis specimens, most similar to P. tompkinsae Andriashev, 1992 (off King George Island, 766–861 m). Paraliparis charcoti Duhamel, 1992 recorded at the eastern part of the Weddell Sea (475–633 m). Paraliparis, most similar to P. tetrapteryx Andriashev et Neelov, 1979, found in the Southwestern Atlantic (1200 m). Four new species are described. Paraliparis porcus sp. nov. based on one male SL 85 mm from off the South Shetland Islands (Elephant Island, 332–374 m). Paraliparis acutidens sp. nov. described from the juvenile SL 115 mm, sampled in the western part of the Scotia Sea (3721–3723 m). Paraliparis kocki sp. nov. known from 3 adults caught in the depression of the Bransfield Strait (1914–1920 m), isolated from the Weddell Sea by shallower waters. The only specimen of the Paraliparis mexicanus sp. nov. collected in the tropical Pacific off Mexico at depth not more than 900 m.     

Molecular identification key based on PCR/RFLP for three polychaete sibling species of the genus <Emphasis Type="Italic">Marenzelleria</Emphasis>, and the species’ current distribution in the Baltic Sea

Studies of Marenzelleria species were often hampered by identification uncertainties when using morphological characters only. A newly developed PCR/RFLP protocol allows a more efficient discrimination of the three species Marenzelleria viridis, Marenzelleria neglecta and Marenzelleria arctia currently known for the Baltic Sea. The protocol is based on PCR amplification of two mitochondrial DNA gene segments (16S, COI) followed by digestion with restriction enzymes. As it is faster and cheaper than PCR/sequencing protocols used so far, the protocol is recommended for large-scale analyses. The markers allow an undoubted determination of species irrespective of life stage or condition of the worms in the samples. The protocol was validated on about 950 specimens sampled at more than 30 sites of the Baltic and the North Sea, and on specimens from populations of the North American east coast. Besides this test we used mitochondrial DNA sequences (16S, COI, Cytb) and starch gel electrophoresis to further investigate the distribution of the three Marenzelleria species in the Baltic Sea. The results show that M. viridis (formerly genetic type I or M. cf. wireni) occurred in the Öresund area, in the south western as well as in the eastern Baltic Sea, where it is found sympatric with M. neglecta. Allozyme electrophoresis indicated an introduction by range expansion from the North Sea. The second species, M. arctia, was only found in the northern Baltic Sea, where it sometimes occurred sympatric with M. neglecta or M. viridis. For Baltic M. arctia, the most probable way of introduction is by ship ballast water from the European Arctic. There is an urgent need for a new genetic analysis of all Marenzelleria populations of the Baltic Sea to unravel the current distribution of the three species.     

Materials on the flora of Bacillariophyta in rivers of the white sea basin in the Republic of Karelia

A total of 290 species and varieties of Bacillariophyta including 32 that were new for the flora of Karelia and 18 that were new for the flora of Russia, have been recorded in phytoplankton in nine rivers of the White Sea basin. The genera Aulacoseira, Pinnularia, Eunotia, and Navicula s. l. are the richest in taxonomy. The maximum species diversity was recorded in the Suma (73), Kolezhma (91), and Chirko-Kem (146) rivers. The following species are the most widespread in the rivers that were under study here: A. ambigua, A. subarctica, A. subborealis, {tiA. tenella}, Asterionella formosa, and Tabellaria flocculosa.     

Revalidation of the Eggvin lumpsucker <Emphasis Type="Italic">Eumicrotremus eggvinii</Emphasis> (Cyclopteridae) and its new finding near Franz Josef Land (Barents Sea)

The species status of a rare species Eumicrotremus eggvinii from the family Cyclopteridae has been revalidated. Some authors considered its specimens as males of close species E. spinosus. In the Zoological Institute collection, males of E. spinosus that are morphologically similar with females of this species have been found. This is evidence of absence of sexual dimorphism in E. spinosus. In new samplings from waters of the Franz Josef Land archipelago (Barents Sea), a specimen of E. eggvinii was found and described. The opinion of some authors that individuals of E. eggvinii represent males of E. spinosus is refuted. A new finding widens the species area to the northeastern limits of the Barents Sea. The number and character of distribution of bone plaques remain reliable taxonomic characters.     

Population structure and variability of Pacific herring (<Emphasis Type="Italic">Clupea pallasii</Emphasis>) in the White Sea,Barents and Kara Seas revealed by microsatellite DNA analyses

Pacific herring, Clupea pallasii, have recently colonised the northeast Atlantic and Arctic Oceans in the early Holocene. In a relatively short evolutionary time, the herring formed a community with a complex population structure. Previous genetic studies based on morphological, allozyme and mitochondrial DNA data have supported the existence of two herring subspecies from the White Sea and eastern Barents and Kara Seas (C. p. marisalbi and C. p. suworowi, respectively). However, the population structure of the White Sea herring has long been debated and remains controversial. The analyses of morphological and allozyme data have previously identified local spawning groups of herring in the White Sea, whereas mtDNA markers have not revealed any differentiation. We conducted one of the first studies of microsatellite variation for the purpose of investigating the genetic structure and relationship of Pacific herring among ten localities in the White Sea, the Barents Sea and the Kara Sea. Using classical genetic variance-based methods (hierarchical AMOVA, overall and pairwise F _ST comparisons), as well as the Bayesian clustering, we infer considerable genetic diversity and population structure in herring at ten microsatellite loci. Genetic differentiation was the most pronounced between the White Sea (C. p. marisalbi) versus the Barents and Kara seas (Chesha–Pechora herring, C. p. suworowi). While microsatellite variation in all C. pallasii was considerable, genetic diversity was significantly lower in C. p. suworowi, than in C. p. marisalbi. Also, tests of genetic differentiation were indicating significant differentiation within the White Sea herring between sympatric summer- and spring-spawning groups, in comparison with genetic homogeneity of the Chesha–Pechora herring.     

Efficiency of three halophyte species in removing nutrients from saline water: a pilot study

Saline wetlands may be well suited for purifying contaminated water from saline agriculture and aquaculture or from freshwater-based agriculture in areas subject to increased salinity. However, case studies on the nutrient removal efficiency of halophyte species are scarce, especially for temperate regions. Here we tested the nutrient removal efficiency and ability to store nutrients in aboveground and belowground biomass of three halophyte species, Aster tripolium, Bolboschoenus maritimus subsp. compactus, and Spartina anglica, in a greenhouse microcosm experiment at two salinity levels. Nutrient removal from water differed among the species: Spartina had the highest nitrogen removal, Bolboschoenus and Spartina had the highest phosphorus removal. The species also differed in the allocation of the nutrient uptake. Bolboschoenus had the highest absolute uptake of nitrogen and phosphorus in shoots, whereas Spartina had the highest uptake of nitrogen and phosphorus in roots. The applicability of these three species in constructed saline wetlands depends on the local salinity and water regime.     

The biogeochemical background and trace metal accumulation by brown algae of the genus <Emphasis Type="Italic">Fucus</Emphasis> in coastal waters of the Sea of Japan,the Sea of Okhotsk,and the White Sea

The ranges of background concentrations of Fe, Mn, Zn, Cu, and Cd in Fucus algae from the Sea of Japan, the Sea of Okhotsk, and the White Sea were determined. The lower background threshold of element concentration was calculated as Me₁₅–2MAD₁₅, the upper background threshold was determined as Me+2MAD. The upper background threshold of the metal contents in Fucus algae can be used as the maximum permissible regional concentration in assessing pollution levels of marine habitats. Comparison of the Me₁₅–2MAD₁₅ values showed that Fucus algae of the White Sea had increased Mn and decreased Cd concentrations compared to those in Pacific algae. The concentrations of Zn were higher in Fucus algae of the Sea of Japan than in macrophytes from the White Sea and the Sea of Okhotsk. The background concentration range of Fe in Fucus algae of the Sea of Japan was much narrower compared to that in their counterparts from the White Sea and the Sea of Okhotsk. The background metal concentrations in Fucus algae are specific to a sea region; their variations are connected not only with the trace element contents in abiotic components of the environment, but also with the functioning of coastal ecosystems.     

The species composition,morphology, and seasonal distribution of diatoms of the genus <Emphasis Type="Italic">Attheya</Emphasis> West, 1860 from the Sea of Japan

Six species that belong to the diatom genus Attheya were found in the Russian waters of the Sea of Japan. A. cf. flexuosa is a new record for the seas of Russia. A. decora is recorded for the first time for the Sea of Japan. The peculiarities of the morphology of A. decora and A. cf. flexuosa are described and illustrated. The study of the seasonal distribution, abundance, and ecology of Attheya species in the northwestern Sea of Japan showed that A. longicornis and A. ussurensis were the most numerous and widespread species, reaching maximum densities (up to 1.5 × 10⁶ and 1.8 × 10⁴ cells/liter, respectively) in the spring, summer, and fall. A. cf. flexuosa and A. septentrionalis were rare and were found in low numbers in the winter and early spring. Based on the ultrastructure of the girdle bands, the form and number of chloroplasts, the presence/absence of rimoportula on the valve, and habitat features, we distinguished two groups of species of the genus Attheya from the Sea of Japan. The first group includes psammophytes A. decora, A. arenicola, and A. ussurensis; the second one comprises A. longicornis and A. cf. flexuosa epiphytic on other diatoms, as well as A. septentrionalis, which is found in the under-ice plankton and is able to attach to the underside of ice.     

Spatial distribution of algae in the <Emphasis Type="Italic">Ahnfeltia tobuchiensis</Emphasis> bed in Amursky Bay (Sea of Japan)

Horizontal and vertical distribution of algae in Ahnfeltia tobuchiensis beds was studied in the area of Mt. Stolovaya in Amursky Bay, Sea of Japan. Thirty-four species of macroalgae (2 species of Chlorophyta, 26 Rhodophyta, and 6 Ochrophyta) were found in the area of study. Two fields of the unattached alga Ahnfeltia were located opposite Mt. Stolovaya; they differed in area, macrophyte stock, number and biomass of attendant species, hydrochemical and light conditions. A monodominant Ahnfeltia tobuchiensis community formed in the southern field and a bidominant community of Ahnfeltia tobuchiensis + Ahnfeltiopsis flabelliformis developed in the northern field. It is suggested that the horizontal distribution of common macrophyte species in the Ahnfeltia beds at Mt. Stolovaya is conditioned by the amount of photosynthetically active radiation (PAR) reaching the surface of the algal bed. Differences in tolerance of Ahnfeltia and attendant species to shadowing and in light conditions across the alga stratum define the vertical distribution of algae within the bed. Chondrus armatus and Ptilota filicina were found mainly in the upper layer of the algal bed. A. tobuchiensis, A. flabelliformis, Chaetomorpha linum, and Coccotylus orientalis extended across the entire thickness of the bed.     

Free-living nematodes of the genus <Emphasis Type="Italic">Alaimella</Emphasis> Cobb 1920 (Nematoda: Leptolaimidae): A description of <Emphasis Type="Italic">A. macramphis</Emphasis> sp. n. from the White Sea and a revision of the genus

Alaimella cincta Cobb 1920 and Alaimella macramphis sp. n. are described and illustrated. Both the species were first recorded for the White Sea in northern Russia. A. cincta occurs in the shells of the agglutinated foraminiferan Reophax curtus, as well as freely in bottom sediments. A. macramphis sp. n. is described from a single male sampled from bottom sediments. A. macramphis sp. n. is distinguished from two previously known species of Alaimella (A. cincta Cobb 1920 and A. truncate Cobb 1920) by having a longer body, longer cephalic setae, and a wide amphid equal to the respective body diameter. The new species also differs from A. truncate by the distinct striation of the cuticular annulations. The Alaimella species are additionally characterized by having a posterior glandular widening of the esophagus. An emended diagnosis of the genus Alaimella Cobb 1920 and a key for species identification are provided.     

Diversity of the microscopic fungi in the littoral sands of the White Sea

For the first time, the study of the mycobiota of littoral sands of the cold-water White Sea was conducted. Twenty-four samples were collected in July–August 2015 in the Onega Bay, the Kandalaksha Bay, and on the Terskii coast. Culture methods were used to detect the number of colony forming units (CFU) and the fungi diversity. The number of CFUs is small; it ranges from 0 to 57 per 1 cm³. A total of 54 morphotypes were detected, of which 22 were identified to the species, seven to the genus level, and 25 were not identified, because they did not form sporulation. Only two species, Cladosorium sphaerospermum and Paradendryphiella salina, were characterized by the relative abundance of more than 10% and the frequency of occurrence of more than 50%. Another five species were found in more than one sample: Penicillium chrysogenum, Cadophora fastigiata, Acremonium fuci, anamorph of Pseudogymnoascus pannorum, and teleomorph of Pseudeurotium hygrophilum. All other morphotypes were found in a small number in single samples. In general, darkcolored forms predominated in the mycobiota both in diversity and in number.     

Population structure and distribution of deep-water cardinal fish <Emphasis Type="Italic">Epigonus occidentalis</Emphasis> (Epigonidae) and <Emphasis Type="Italic">Epigonus pandionis</Emphasis> (Epigonidae) in the Colombian Caribbean Sea

Cardinal fish are commercially valuable species. In the Colombian Caribbean Sea E. occidentalis and E. pandionis occurred in 37and 35% of tows during a research trawl survey (>200 m), respectively and the biology of these vulnerable species is unknown. The aim of this work is to describe the spatial distribution patterns of biomass, size structure and morphometric relationships of E. occidentalis and E. pandionis in deep waters of the Colombian Caribbean Sea. The samples were collected by trawling in depths between 200 and 550 m. No statistical differences were found in size by sexes in both species. In female and male E. occidentalis the growth was isometric, while in female and male E. pandionis it was positive allometric. E. occidentalis occurred mainly in the northern zone of Colombian Caribbean Sea, with highest aggregations off Santa Marta and Riohacha. E. pandionis was distributed in the northern area between Santa Marta and Riohacha and in the southern area between Cartagena and Morrosquillo Gulf. However, before the exploitation of these species is considered, further research is required to determine basic life history traits, such as growth, reproduction, recruitment, and mortality.     

Molecular genetic markers of intra- and interspecific divergence within starfish and sea urchins (Echinodermata)

A fragment of the mitochondrial COI gene from isolates of several echinoderm species was sequenced. The isolates were from three species of starfish from the Asteriidae family (Asterias amurensis and Aphelasterias japonica collected in the Sea of Japan and Asterias rubens collected in the White Sea) and from the sea urchin Echinocardium cordatum (family Loveniidae) collected in the Sea of Japan. Additionally, regions including internal transcribed spacers and 5.8S rRNA (ITS1–5.8S rDNA–ITS2) were sequenced for the three studied starfish species. Phylogenetic analysis of the obtained COI sequences together with earlier determined homologous COI sequences from Ast. forbesii, Ast. rubens, and Echinocardium laevigaster from the North Atlantic and E. cordatum from the Yellow and North Seas (GenBank) placed them into strictly conspecific clusters with high bootstrap support (99% in all cases). Only two exceptions–Ast. rubens DQ077915 sequence placed with the Ast. forbesii cluster and Aph. japonica DQ992560 sequence placed with the Ast. amurensis cluster–were likely results of species misidentification. The intraspecific polymorphism for the COI gene within the Asteriidae family varied within a range of 0.2-0.9% as estimated from the genetic distances. The corresponding intrageneric and intergeneric values were 10.4-12.1 and 21.8-29.8%, respectively. The interspecific divergence for the COI gene in the sea urchin of Echinocardium genus (family Loveniidae) was significantly higher (17.1-17.7%) than in the starfish, while intergeneric divergence (14.6-25.7%) was similar to that in asteroids. The interspecific genetic distances for the nuclear transcribed sequences (ITS1–5.8S rDNA–ITS2) within the Asteriidae family were lower (3.1-4.5%), and the intergeneric distances were significantly higher (32.8-35.0%), compared to the corresponding distances for the COI gene. These results suggest that the investigated molecular-genetic markers could be used for segregation and identification of echinoderm species.