[Dynamics of parasite communities in an age series of Arctic Cisco Coregonus migratorius (Georgi, 1775)].

Parasite communities of Arctic cisco from Chivyrkui Bay of Lake Baikal have been analyzed at levels of a host individual (infracommunity), a individual age group of a host-(assemblages of infracommunities), and a host population (component community). Significant positive correlations of parameters of species richness (number of parasite species, Margalef and Menhinick indices) with the age of Arctic cisco were recorded only at the level of parasite inffacommunities. The absence of linear positive correlations between the parameters of species richness and the age of Arctic cisco at the level of assemblages of parasite infracommunities were revealed for the first time for fish of Lake Baikal.

[Tapeworm Oochoristica tuberculata (Rudolphi, 1819)--parasite of the lizard Eremias argus Peters, 1869 in Zabaikalie].

Morphological characteristics of the tapeworm Oochoristica tuberculata from the lizard Eremias argus is given from the northern border of the host areal. The complexes of most stable and most variable characters of this tapeworm are determined. The list of hosts is given for Oochoristica tuberculata.

[Composition of leucocytes of the head kidney of the crucian carp Carassius auratus gibelio (Cypriniformes: Cyprinidae) as affected by invasion of cestode Digramma interrupta (Cestoda; Pseudophyllidea)].

The composition of leucocytes of the head kidney is studied in the crucian carps (Carassius auratus) either contaminated or uncontaminated with Digramma interrupta. The composition of leucocytes in the pronephros of the crucian carp from Lake Baikal basin has a lymphoid character. Compared to the crucian carp from the European part of Russia, in the fish from Baikal the granulocytopoetic processes are more pronounced.

[Characteristics of karyotype structure in Phyllodistomum umblae (Trematoda: Gorgoderidae) from Lake Baikal].

Haploid complement of Phyllodistomumn umblae ex baikal whitefish from Lake Baikal consists of 8 chromosomes (6 metacentrics and 2 submetacentrics). The significant difference is observed in the ratio of acrocentrics and metacentrics in the haploid set of chromosomes between isolated populations of P. umblae from Baikal region and from Chukotka.

[Baikal whitefish Coregonus baicalensis Dybowski, 1874 parasite communities and host age].

Data on the taxonomic diversity of Baikal whitefish parasites are summarized in the study. Significant correlations of some parasite species' relative abundance and parasite communities' (infracommunities and component communities) parameters with host age were found during the study of parasite distribution in the host's age groups in the Baikal whitefish population from Chivyrkui Bay of Lake Baikal. Study of morphobiological and genetic features which have arisen due to long-term geographic isolation allowed confirming the initial specific independence of lake whitefishes of Lake Baikal as Coregonus baicalensis Dybowski, 1874, i.

[Distribution of Aspidogaster conchicola (Aspidogastrea, Aspidogastridae) in the organism of Colletopterum spp. (Bivalvia, Unionidae) of different age from the Chivyrkuiski Gulf of Lake Baikal].

Distribution of Aspidogaster conchicola Baer, 1827 in the organisms of its hosts Colletopterum spp. from the Chivyrkuiski Gulf of Lake Baikal was investigated. The number of A.

[The morphological variability of the maritae of Phyllodistomum umblae and Phyllodistomum folium (Trematoda: Gorgoderidae) from fish in the Lake Baikal basin].

The host variability of adults of Phyllodistomum umblae and P. folium in fishes of the Baikal region has been studied. The absence of considerable geographical variability of P.

[The distribution of Phyllodistomum umblae and Phyllodistomum folium (Trematoda: Gorgoderidae) in the excretory system of fishes].

It is shown, that the distribution of Phyllodistomum umblae in the excretory system of all investigated species of salmonids has a principal similarity. The distribution of P. umblae in the excretory system of the Siberian dace and the Siberian roach is distinguished from that of P.