Branchiobdellida (Oligochaeta) from the farthest South-East of the U.S.S.R.

Eight species of the genera Branchiobdella and Cirrodrilus are reported from the Soviet Far East. Six of them from the Komarovka Stream in the Ussuriiski State Nature Reserve: Branchiobdella cheni (Liu, 1964), B. domina sp.n., Cirrodrilus chosen (Yamaguchi, 1934), C. suzukii (Yamaguchi, 1934), C. pugnax sp.n., and C. fimbriatus sp.n. Branchiobdellidans are abundant in this stream, occurring on the crayfishes Cambaroides dauricus wladiwostokensis as well as in benthic samples. Two from the northern Amur River basin near Khabarovsk: Branchiobdella minuta Pierantoni, 1912, and Cirrodrilus quadritentacularis (Liu, 1984), living on the crayfishes Cambaroides dauricus dauricus and C. schrencki . The genus Cirrodrilus demonstrates several trends of parallel variation on the Asian continent and the Japanese Islands; the more apomorphic genus Branchiobdella seems to be absent in Japan.