Population structure of arctic lamprey Lethenteron camtschaticum from the Kol River (Western Kamchatka)

Phenetic diversity is investigated and the taxonomic status of lampreys (Petromyzontidae) from the Kol basin (Western Kamchatka) is verified. Typically anadromous lamprey, anadromous lamprey forma praecox, resident lamprey, smolts, and larvae of lamprey are discovered and described. Their comparative analysis is made by standard morphometric characters. Differences between the forms by plastic characters depend on size and weight. No significant differences are found by major taxonomic characters between the forms of anadromous and resident lampreys which would indicate their taxonomic separation. Phenetic types of spawners are representatives of the population of one complexly structured species represented by life forms realizing different life history strategies (anadromous and resident), and belong to the species Arctic lamprey Lethenteron camtschaticum (Tilesius, 1811).