General patterns of macrozoobenthos distribution in two rivers basins of the Khabarovsky Krai (Far East of Russia)

This article analyses the distribution patterns of macrozoobenthos in watercourses of the basins of the River Bajal and River Anyuy (Khabarovsky Krai, Russia) on the territories of the Bajal Sanctuary and Anyuy National Park. The distance-based linear models (DistLM) method was used to estimate the proportion of distribution of macroinvertebrates explained by the factors considered in the study (river basin, current velocity, substrate, channel width, temperature, pH). All of these factors contributed significantly, together explaining about one-third of the variability of macroinvertebrate distribution. The main explanatory factors were river basin and substrate (9.3% and 10.5%, respectively), as well as the current velocity (5.7%). Based on the cluster analysis, eight statistically significant groups of samples on the basis of similarity of taxonomic composition were identified. A set of indicator taxa was determined for each group and their indicator values were found. Using the Kruskal-Wallis analysis, the environmental factors significantly differing between the obtained groups and subgroups were singled out. There are well-defined patterns in the confinement of taxonomic complexes to certain habitats. Local environmental factors are the strong filter influencing the formation of taxonomic communities. The factor of belonging to the river basin also plays a significant role in the formation of invertebrate communities, which should be considered in the planning of monitoring studies on a large spatial scale. However, the distinguished groups and subgroups are characterised by a low level of internal similarity. Only about a quarter of the total species number belongs to indicator taxa, and samples do not form discrete clusters with obvious hiatus on the ordination diagram. The longitudinal distribution of macroinvertebrates for each river can be characterised as a punctuated gradient

Assemblages of Meiobenthic and Planktonic Microcrustaceans (Cladocera and Copepoda) from Small Water Bodies of Mountain Subarctic (Putorana Plateau, Middle Siberia)

The Putorana Plateau (Krasnoyarsk Territory, Russia) is one of the largest mountainous regions of subarctic Eurasia. Studies of aquatic ecosystems of this are far from complete. In particular, microcrustaceans (Cladocera и Copepoda) of the Putorana Plateau are poorly investigated, although they are one of the main components of meiobenthic and zooplanktonic communities and a target for monitoring of the anthropogenic influence and climate change. An open question is a biogeographical status of the crustacean fauna of the plateau. Additionally, it is unknown which environmental factors significantly affect benthic and planktonic crustacean assemblages? Based on the samples collected in tundra and forest tundra ponds in the western and central parts of the plateau, analysis of the composition of crustacean fauna and factors regulating the assemblage structure was performed. In total, 36 Cladocera and 24 Copepoda species were found. Of these, 23 taxa are new for the region, and four are new to science. Species richness of Copepoda is higher in the central part and on the western slopes of the plateau than in foothills, while number of the Cladocera species in contrast decreases in mountainous areas. Variations in meiobenthic assemblages are due to the research area, type of water supply and less affected by altitude above sea level. For planktonic assemblages the size of the water body and, to a lesser degree, by macrophytes species composition was significant. Almost 12.8% of microcrustacean species of the Putorana Plateau can be attributed to glacial relics. Crustacean fauna of the Putorana Plateau has a high species richness and distinguishes significantly from the fauna of both western and eastern regions of the Arctic. The specifics of faunal composition of the region are connected to the climatic features of Middle Siberia and the retaining of the Pleistocene fauna in some glacial refugia

Meiofauna: Biodiversity, Ecology, and Role in Ecosystems

The meiofauna is currently considered to be a group of microscopic metazoans ranging in size from 30 to 1000–2000 μm, forming a distinct size class [...

A new species of <i>Breviconia</i> Conroy-Dalton & Huys, 2000 (Copepoda: Harpacticoida: Ancorabolidae Sars) from the Bering Sea, northern Pacific Ocean (Russia)

The finding of Breviconia andrei sp. nov. in the Russian Bering Sea enabled the clear-cut phylogenetic characterization of the former monotypic genus Breviconia Conroy-Dalton &amp; Huys, 2000 as a monophylum. Comparison of the new species with B. australis (George, 1998) and other members of the subfamily Ancorabolinae Sars, 1909 yielded four autapomorphies that unambiguously support the monophyletic state of Breviconia: (1) an elongated and approximately 90°-curved mandibular gnathobase, (2) reduction of the maxillar endopod, (3) maxillar endites carrying 2 instead of 3 setae, and (4) loss of the minute seta on the maxillipedal claw. For B. andrei sp. nov., two autapomorphies could be detected, namely, (1) the development of dorsal tubercles on the P5-bearing body somite and (2) the remarkable elongation of the first endopodal segment of the first swimming leg that is twice as long as the whole exopod. Of particular interest is the presence of a 3-segmented endopod in the third swimming leg of the male of B. andrei sp. nov. It disproves the current assumption that the Ancorabolinae are characterized by (among others) the derived presence of an only 2-segmented endopod in the male’s third swimming leg.</p

Figure 3 in Fauna of microcrustaceans (Cladocera: Copepoda) of shallow freshwater ecosystems of Wrangel Island (Russian Far East)

Figure 3. Simplified map of the compared regions.Published as part of Novichkova, Anna A. & Chertoprud, Elena S., 2015, Fauna of microcrustaceans (Cladocera: Copepoda) of shallow freshwater ecosystems of Wrangel Island (Russian Far East), pp. 2955-2968 in Journal of Natural History 49 (45) on page 2961, DOI: 10.1080/00222933.2015.1056269, http://zenodo.org/record/400237

Crustaceans in the Meiobenthos and Plankton of the Thermokarst Lakes and Polygonal Ponds in the Lena River Delta (Northern Yakutia, Russia): Species Composition and Factors Regulating Assemblage Structures

Information about invertebrates in the low-flow water bodies of northeastern Siberia is far from complete. In particular, little is known about crustaceans—one of the main components of meiobenthic and zooplanktonic communities. An open question is which environmental factors significantly affect the crustaceans in different taxonomic and ecological groups? Based on the data collected on the zooplankton and meiobenthos in the tundra ponds in the southern part of the Lena River Delta, analysis of the crustacean taxocene structure was performed. In total, 59 crustacean species and taxa were found. Five of these are new for the region. The species richness was higher in the large thermokarst lakes than in the small water bodies, and the abundance was higher in small polygonal ponds than in the other water bodies. Variations in the Cladocera assemblages were mainly affected by the annual differences in the water temperature; non-harpacticoid copepods were generally determined by hydrochemical factors; and for Harpacticoida, the macrophyte composition was significant. Three types of the crustacean assemblages characteristic of different stages of tundra lake development were distinguished. The hypothesis that the formation of crustacean taxocenes in the Lena River Delta is mainly determined by two types of ecological filters, temperature and local features of the water body, was confirmed

Figure 4 in Fauna of microcrustaceans (Cladocera: Copepoda) of shallow freshwater ecosystems of Wrangel Island (Russian Far East)

Figure 4. Dendrogram for hierarchical clustering (group average) of faunas of different arctic regions.Published as part of Novichkova, Anna A. & Chertoprud, Elena S., 2015, Fauna of microcrustaceans (Cladocera: Copepoda) of shallow freshwater ecosystems of Wrangel Island (Russian Far East), pp. 2955-2968 in Journal of Natural History 49 (45) on page 2962, DOI: 10.1080/00222933.2015.1056269, http://zenodo.org/record/400237

Two new species of Bryocamptus (Copepoda, Harpacticoida, Canthocamptidae) from the Russian Arctic and comparison with Bryocamptus minutus (Claus, 1863)

Two new species of Bryocamptus Chappuis, 1929 from the Russian Arctic from the Bryocamptus minutus species group are described: Bryocamptus putoranus sp. nov. and Bryocamptus abramovae sp. nov. A complete morphological comparison of the new species with the type species Bryocamptus minutus (Claus, 1863) was carried out. Significant interspecific differences were shown at the level of microcharacters, such as integumental sensillae and pores, ornamentation of segments of mouthparts and swimming legs, and pores on swimming legs. A significant correlation has also been shown in the shape of the caudal rami of the females and the antennules of the males, which is likely caused by an evolutionary sexual arms race. Bryocamptus putoranus sp. nov. and B. minutus have a similar structure of caudal rami, but completely different male antennules, which may indicate a convergent origin of modifications and highlights the importance of depicting male antennules in the species descriptions

FREMONEC: Effect of climate change and related stressors on fresh and brackish water ecosystems in Svalbard. A Norwegian and Russian joint scientific project

Dimante-Deimantovica, I., Chertoprud, M., Chertoprud, E., Christoffersen, K.S., Novichkova, A. & Walseng, B. 2015. FREMONEC: Effect of climate change and related stressors on fresh and brackish water ecosystems in Svalbard. A Norwegian and Russian joint scientific project. - NINA Report 1218. 40 pp. This report summarizes the results of the Russian-Norwegian collaboration project FREMONEC which was established as part of POLRES (Polar Research sub-program NORRUSS) with the aim to stimulate bilateral cooperation on polar research. Researchers from The Norwegian Insti-tute for Nature Research and M. V. Lomonosov Moscow State University have studied the effects of climate change and related stressors on fresh and brackish water habitats, by using inverte-brates as biological quality elements. Both partners were involved in preparing the study design, as well as participating in meetings, fieldwork (2014 and 2015) and analyzing/reporting of col-lected material. Altogether, 75 localities in Isfjorden and Kongsfjorden areas, including both lotic and lentic waters, were sampled. pH varied between 6.2 and 9.5 and conductivity from < 0,01 to ˃ 10000 μS/cm. In general, biodiversity was low, especially when we compare Svalbard with other areas in the high and low Arctic. Still this survey revealed 6 microcrustacean taxa new to Svalbard: Polyphemus pediculus, Diaptomidae sp., Diacyclops abyssicola, Epactophanes rich-ardi, Nitokra spinipes and Geeopsis incisipes. Most likely, some of these newcomers are directly or indirectly linked to the recent climate warming (obtained results were compared with old liter-ature data). For macrozoobenthos it seemed that the origin of habitat, temperature, substrate type and water velocity were of importance. The number of crustaceans increased with the age of the localities (distance to the retreating glacier). For instance, the youngest habitats close to the glacier had the lowest number of copepod species and no cladocerans. The fauna in ‘urban’ ponds near human settlements did not differ from non-urban habitats. In the urban ponds, birds seem to be a more important factor than anthropogenic activities, contributing to diversity. As part of this project, one bachelor and one PhD student completed their theses. The network building between Norwegian and Russian research groups, which has included thematic areas relevant for both countries, has been a positive experience for both partners. Further, new knowledge on Svalbard’s biodiversity might give a contribution to future Arctic Freshwater Biodi-versity Monitoring activities and to the implementation of integrated and sustainable Arctic fresh-water ecosystems management. Because of FREMONEC, new collaboration projects and dis-semination activities have also been initiated (projects NORUSVA and BRANTA-DULCIS)

A new species of Breviconia Conroy-Dalton & Huys, 2000 (Copepoda: Harpacticoida: Ancorabolidae Sars) from the Bering Sea, northern Pacific Ocean (Russia)

The finding of Breviconia andrei sp. nov. in the Russian Bering Sea enabled the clear-cut phylogenetic characterization of the former monotypic genus Breviconia Conroy-Dalton & Huys, 2000 as a monophylum. Comparison of the new species with B. australis (George, 1998) and other members of the subfamily Ancorabolinae Sars, 1909 yielded four autapomorphies that unambiguously support the monophyletic state of Breviconia: (1) an elongated and approximately 90°-curved mandibular gnathobase, (2) reduction of the maxillar endopod, (3) maxillar endites carrying 2 instead of 3 setae, and (4) loss of the minute seta on the maxillipedal claw. For B. andrei sp. nov., two autapomorphies could be detected, namely, (1) the development of dorsal tubercles on the P5-bearing body somite and (2) the remarkable elongation of the first endopodal segment of the first swimming leg that is twice as long as the whole exopod. Of particular interest is the presence of a 3-segmented endopod in the third swimming leg of the male of B. andrei sp. nov. It disproves the current assumption that the Ancorabolinae are characterized by (among others) the derived presence of an only 2-segmented endopod in the male’s third swimming leg