Salmincola markewitschi (Copepoda: Lernaeopodidae) Parasitic on Whitespotted Char, Salvelinus leucomaenis, in a Mountain Stream of Honshu Island, Central Japan

Abstract

Females of the lernaeopodid copepod Salmincola markewitschi Shedko and Shedko, 2002 were collected from the buccal cavity of whitespotted char, Salvelinus leucomaenis (Pallas, 1814), in a mountain stream of Nagano Prefecture, Honshu Island, the largest main island of Japan. The females are described as the first record of S. markewitschi from Honshu Island, because the species has so far been reported from the Russian Far East and the southern Kuril Islands east of Hokkaido Island, Japan. The copepod previously reported as Salmincola californiensis (Dana, 1852) from the same host species from the same stream and a nearby hatchery is herein regarded as S. markewitschi. As the species closely resembles Salmincola carpionis (Krøyer, 1837), it is desirable to re-identify the copepod specimens reported before as S. carpionis from Japanese salmonids, especially Salvelinus spp. Contraction of the formalin-fixed and preserved specimens, especially their second maxillae, of S. markewitschi is discussed. Information on the known hosts and distribution records of S. markewitschi is also compiled.