Diversity and Distribution of Free-living Ciliates from High-Arctic Kara Sea Sediments.

For the first time, free-living ciliates were studied in sediments from a variety of habitats in the Kara Sea (the Arctic Ocean). Ciliates were found in a wide range of environmental conditions (from the intertidal zone up to depths of 554m, from salinities ranging from 0 to 34psu, and from coarse sands and gravel to muddy sediments), with total abundances varying from 1 to 127ind/cm. Altogether, 114 species were identified, most of which were widely distributed and were previously reported from other Arctic regions.

An Estimation of the Global Diversity and Distribution of the Smallest Eukaryotes: Biogeography of Marine Benthic Heterotrophic Flagellates.

Protists are ubiquitous, but the factors influencing their diversity and biogeography remain unclear. We use a comprehensive database on the marine benthic heterotrophic flagellate (HF) morphospecies to explore the worldwide patterns in their diversity and distribution in comparison with predictions of the Ubiquity model (UM) and Moderate Endemicity model (MEM). The number of known HF morphospecies was limited (even when considering the rates of descriptions), and the local-to-global diversity ratio was relatively high (10-25%).

Composition, diversity and distribution of microbenthos across the intertidal zones of Ryazhkov Island (the White Sea).

The composition and distribution of the main unicellular eukaryotic groups (diatom algae, ciliates, dinoflagellates (DF), other phototrophic (PF) and heterotrophic flagellates (HF)) were investigated in sandy sediments at five stations allocated across the tidal sheltered beach of the White Sea. Overall, 75 diatoms, 98 ciliates, 16 DF, 3 PF and 34 HF species were identified; some are new records for the White Sea. Common species for each group are illustrated.

Cryptic diversity of the 'cosmopolitan' harpacticoid copepod Nannopus palustris: genetic and morphological evidence.

Nannopus palustris Brady, 1880 is a free-living widely distributed harpacticoid copepod, which has been formerly assumed to be a single, cosmopolitan but highly variable species. We compared several geographically distant N. palustris populations in terms of their morphology and genetics.