Early Ontogenetic Features in the White Charr Salvelinus malma Complex (Salmonidae) from Lake Kronotskoe, Eastern Kamchatka

Abstract

The growth, the sequence of formation, and the features of the transitive states of skeletal elements (cranial bones and serial structures, such as teeth, gill rakers, fin rays and pterygiophores, vertebral bodies, predorsalia, and scales) have been studied in prelarvae, larvae, and fingerlings of the lacusrtrine-riverine morphs of the white charr Salvelinus malma complex from Lake Kronotskoe, Eastern Kamchatka, reared in a laboratory at a constant temperature and collected in the Uzon River, at a spawning ground and downstream. A comparative analysis of osteogenesis features in white charr and the original morph, the Northern Dolly Varden Salvelinus malma malma, has been carried out. A high variability in the rate of growth and development of white charr is noted. A delay in calcification of skeleton in prelarvae and a late onset of scale formation (at the end of the second and the beginning of the third year of life) and first annulus in otoliths (by the third year of life) have been revealed. The results indicate the high specialization of early ontogenesis in white charr, a fish endemic to Lake Kronotskoe.