Two Lineages of Oribatid Mites Morphologically Correspond to the Circumpolar Species Ameronothrus nigrofemoratus (Acari, Oribatida) but Differ Genetically as Distinct Species Are Revealed on the Kolguev Island.

Data reported from Northern Canada were until recently the only available data on the genetic characteristics of the oribatid mite Ameronothrus nigrofemoratus, which has a circumpolar distribution on the coasts of Arctic seas. A partial cytochrome oxidase I gene (COI) mtDNA sequence was examined in mites morphologically assigned to this species from the Kolguev Island. Two highly divergent phylogenetic lineages of A.

The Center of Origin and Colonization Routes of Noble Salmons of the Genus Salmo (Salmonidae, Actinopterigii).

Genetic diversity and colonization routes of noble salmons were studied using a partial nucleotide sequence of the mitochondrial COI gene. The brown trout S. trutta, which is the most ancient species of the genus, was concluded to originate from the modern southeastern Pontic-Caspian area, which is currently inhabited by members of the subspecies S.

Polyunsaturated Fatty Acid Content in Muscle Tissue Is Associated with the Duration of Embryo Development in Salmonoid Fishes (Salmonoidei).

A hypothesis was advanced and grounded that the total content of eicosapentaenoic (EPA, 20:5n-3) and docosahexaenoic (DHA, 22:6n-3) acids in fish muscle tissue is associated with the species-specific (taxon-specific) duration of embryo development. A meta-analysis of the original and published data was performed using fishes of the families Coregonidae and Salmonidae as an example. Fishes with longer embryo development times, which are observed at lower temperatures, were found to have significantly higher EPA + DHA contents in muscles as compared with the species that belong to the same families but have shorter embryo development times.

Resident and Anadromous Forms of Arctic Charr (Salvelinus alpinus) from North-East Europe: An Example of High Ecological Variability without Speciation.

Samples from 11 populations of the Arctic char of the North-European part of Russia belonging to the anadromous and resident forms and two samples from Lake Sobach'e (Taimyr) were studied. The nucleotide sequence of the mitochondrial COI gene was determined in 60 individuals. In the majority of populations, the same COI haplotype was found.

Fish hosts, glochidia features and life cycle of the endemic freshwater pearl mussel Margaritifera dahurica from the Amur Basin.

Margaritiferidae is a small freshwater bivalve family with 16 species. In spite of a small number of taxa and long-term history of research, several gaps in our knowledge on the freshwater pearl mussels still exist. Here we present the discovery of host fishes for Margaritifera dahurica, i.