Species Diversity

Abstract

The lernaeopodid copepod Tracheliastes sachalinensis Markevich, 1936 was found on the fins of three species of the sub-family Leuciscinae Bonaparte, 1846 (Cypriniformes: Cyprinidae): big-scaled redfin, Tribolodon hakonensis (Günther, 1877); Sakhalin redfin, Tribolodon sachalinensis (Nikolskii, 1899); and lake minnow Rhynchocypris percnurus (Pallas, 1814); collected in three lakes (Lake Tôro, Lake Shirarutoro, and Lake Abashiri) and two rivers (Mena River and Jirô-sawa River), Hokkaido, northern Japan. These findings represent the first records of Tracheliastes sachalinensis from Japan and also from outside of Russia, in which the copepod has hitherto been found. The species is specific to leuciscine fishes in the subarctic region of the Russian Far East and Japan. We also provide a review of parasitic copepods of freshwater fishes from Hokkaido.