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Charrs of the genus Salvelinus from the ultraoligotrophic Lake Dal'nee Maar differ from anadro mous Dolly Varden S. malma in larger head with elongated jaws, larger gill cover, lower body with a deep cau dal peduncle and short pelvic fins displaced anteriorly, larger number of scales in the lateral line, and larger number of rays in the unpaired fins. The lacustrine charrs also differ from the maternal Dolly Varden popu lation in longer free part of the maxilla, lower widths of the opercular bones, and narrower suspensorium. Polymorphism of mtDNA is low, and unique haplotypes of the D loop control region are not revealed. The life span of the lacustrine charrs reaches 11 years; and their maximum length and weight are 47 cm and 820 g. The spawning is registered in the fall at the slope of the bottom near the mouth of the single stream flowing into the lake. The abundance of the spawning group slightly exceeds 1000 individuals. This group is recruited from offspring migrating during their early life to the stream with limited food resources, and more numerous progeny remaining in the lake do not reach sexual maturity. The main food sources of adult charrs during summer are planktonic crustaceans, imago of insects, and own juveniles.

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Residential form of white spotted char Salvelinus leucomaenis appears in volcanic stream charac terized by stable water and temperature regime. The maximal body length of fish is 285 mm and body mass is 245 g; the oldest specimen is 7 years old. The somatic growth does not relax, and the annual growth rate is 30-40 mm. The maturation begins at the age of 4 years after the fish reaches 175 mm length and 60 g in weight. The spawning takes place in autumn. Sex dimorphism and nuptial coloration are not observed, and the "spotted" coloration remains through the year. Vomer is toothless, or only one tooth is presented (in 15% of sampled specimens). Sagittal otoliths are characterized by deformation granular texture of ventral area, the layering is broken. The food spectra of a mature specimen comprises gammarids, large size larvae, and ima goes of amphibiotic insects during the summer period.

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