Kamchatkan rainbow trout

The Kamchatkan rainbow trout ("mikizha") comprises various ecological forms, including anadromous and resident freshwater forms and their intermediates.[5][6] Russian taxonomy has long attributed the rainbow trout to the genus Parasalmo, and has further considered the Kamchatkan rainbow trout as composed of two distinct species, Parasalmo mykiss and Parasalmo penshinensis, whose ranges overlap. P. mykiss is a resident freshwater and estuary form, whereas P. penshinensis, "Kamchatkan salmon", is the sea-run, migrating anadromous form, which may grow to a length of 100 cm and 11–12 kg weight (as with the American steelhead).[7] P. penshinensis is considered critically endangered (CR) in the Red Book of Kamchatka.[7][5] Modern research however suggests that the two forms represent the same species, showing no genetic isolation or differences.[5][8]