Special Traits in Early Ontogenesis of the Endemic Lacustrine Form of the Salvelinus malma Сomplex (Salmonidae), Small-Mouth Form, from Lake Kronotskoe (Eastern Kamchatka)

Abstract

Growth, sequences of anlage, and special traits of transient states are investigated in skeletal elements (skull bones and serial structures—teeth, gill rakers, fin rays and pterygiophores, vertebral centra, predorsalia, scales) in prolarvae, larvae, and fry of endemic lacustrine form Dolly varden Salvelinus malma сomplex from Lake Kronotskoe in small-mouth char grown in a laboratory at constant temperature. A high individual variation of growth rate, osteogenesis, and head profile of small-month char larvae is observed demonstrating a recent, in relation to other endemic Kronotskoe Lake forms, formation of this deep-water lacustrine morphotype. Comparative analysis in early development of sympatric small-mouth and white char indicated the origin of the more warm-water, small-mouth char from the cold-water white char.