Distribution and prevalence of a myxosporean parasite, Myxidium rhodei Leger, 1905, infecting two cyprinid fish, a roach Rutilus rutilus and Siberian dace Leuciscus leuciscus baikalensis, have been studied in water bodies of the Lake Baikal basin. Over 15-year period (1998-2013), a total of 246 roaches and 189 daces from 27 stations were surveyed. Plasmodia of M. rhodei were registered in the Bowman’s capsules and interstitials in fish kidneys. M. rhodei was recorded in roach and dace almost in all studied water bodies and rivers of the Lake Baikal basin, except Lake Ugii-Nur and the northern part of Lake Khovsgol. Infection intensity of roaches was significantlyhigher in Lake Baikal than in rivers and lakes of the basin. Benthophagous roaches displayed significantly higher infection intensity than euryphagous daces.
A new Thecacineta species (Ciliophora, Suctorea) on Desmodora pontica (Nematoda, Desmodorida) from a seagrass bed in Taiwan
Jian-Xiang Liao, Igor Dovgal
A suctorian ciliate Thecacineta urceolata sp. nov. is described from the sediment specimens collected in a seagrass bed at Ludao, Taiwan. The suctorian was found colonizing the body surface of nematode Desmodora pontica. The new species differs from relatives, Thecacineta cothurnioides and Thecacineta oregonensis, in the lorica structure, which characteristic by the urceolate apical part.
Spatial and temporal variability of seaweeds at Hwadang-ri, Jinhae Bay, Korea
Man Kyu Huh
The study describes seasonal patterns and spatial distribution of seaweeds at five stations at Hwadang-ri, Jinhae Bay (Korea) in 2013. The seaweed community at Hwadang-ri was very diverse, with 44 taxa identified, representing three phyla: brown algae (phylum Ochrophyta), red algae (phylum Rhodophyta), and green algae (phylum Chlorophyta). Red algae exhibited the greatest diversity (26 taxa), followed by brown algae with 11 taxa, and green algae (represented by 7 taxa). The near seaside stations were characterized by the relatively higher individual density or abundance across areas than the stations in the open sea. Five species (Ulva pertusa, Sargassum fulvellum, Sargassum horneri, Sargassum thunbergii, and Undaria pinnatifida) dominated in terms of relative abundance. For the entire community, the values of temporal heterogeneity were low at the open sea stations and higher at the others. Overall, the results indicate that spatial heterogeneity in species composition among the replicates was not high. However, distribution of abundance of seaweeds showed statistically significant north-south differences at the studied sampling sites.
Microbial genetic diversity in soils along salinealkaline gradients at the coast of Laizhou Bay
Feng Zhao, Kuidong Xu
The soils along the coast of Laizhou Bay in China have suffered serious salinization due to natural reasons and anthropogenic effects, and thus represent a salt-affected environment. Using denaturing gradient gel electrophoresis (DGGE) and gene sequencing, we investigated the genetic diversity of microorganisms in relation to environments, in particular soil salinity (0.1-19 psu) and pH (7.9-10) at five sites in the coastal soils of the Changyi National Marine Specific Protection Area and an adjacent idle salt field. There were obvious shifts of both the microeukaryotic and prokaryotic communities along the environmental gradients. The sequencing of microeukaryotic bands uncovered highly diverse groups which were primarily dominated by Cercozoa. The sequences of Cercomonadida were detected for the first time from highly saline soils (about 19 psu), while the upper limit of Cercomonadida in saline soil and aquatic environments detected by previous studies was 5 psu. The sequencing of bacterial bands revealed the presence of Proteobacteria at all sites, whereas Acidobacteria were only detected at sites with low salinity and high pH. Cluster analysis of both microeukaryotic and prokaryotic DGGE profiles classified the five sites into three main groups, which was consistent with the analysis based on both the environmental factors and the abundance of diatoms, ciliates, testate amoebae and nematodes. Statistical analyses indicated that soil salinity was the primary factor in regulating the microbial genetic diversity, while the combination of pH and phosphorous content was the most important factor in explaining the changes of microeukaryotic and prokaryotic communities along the environmental gradients in the coastal soils.
Collection of the proteus-type amoebae at the Institute of Cytology, Russian Academy of Sciences. II. Index of strains and list of publications
Andrew Goodkov, Alexander Yudin, Yuliya Podlipaeva
Previously, in the first part of publication (Goodkov et al., 2014) we had presented and described the collection of free living freshwater amoeba strains of Amoeba proteus-type (family Amoebidae), the collection being for a long time maintained in the Institute of Cytology RAS, Saint-Petersburg, Russia. This collection is named Amoebae Culture Collection at the Institute of Cytology (ACCIC). In the second part of collection description (the present publication) we quote the full list of amoebae strains maintaining today in the Collection with their passports containing the date of the strain acceptance, whom it was received from, when and where the strain was isolated from, notes, and the full register of articles where these strains were used as research objects (bibliography).