抄録
The fauna and distribution of blackflies in Yamaguchi Prefecture, Japan, were studied based on the collections of larvae and pupae from streams at 72 sites in spring of 1984. A total of 8, 124 blackflies, [7, 000 larvae (86.2% in total number) and 1, 124 pupae (13.8%)], were collected at 72 sites. All these blackflies were classified into 15 species of two genera : Prosimulium Roubaud and Simulium Latreille. Eight species, Simulium (Nevermannia) aureohirtum, S. (N.) mie, S. (N.) subcostatum, S. (Simulium) japonicum, S. (S.) nikkoense, S. (S.) quinquestriatum, S. (S.) rufibasis and S. (S.) suzukii were newly recorded from Yamaguchi Prefecture. Further two species were undescribed and/or unidentified species, e.g. Eusimulium sp. 2 and S. sp. H. The most abundant species was S. (N.) uchidai (29.5% in total number), followed by S. (S.) arakawae (26.0%), S. (N.) subcostatum (15.6%), S. (S.) japonicum (13.2%) and S. (Gnus) bidentatum (4.6%). The most widely distributed species was S. (N.) uchidai (64 sites), followed by S. (N.) subcostatum (62 sites), S. (S.) japonicum (43 sites), S. (S.) arakawae (37 sites), S. (S.) nikkoense (24 sites), S. (N.) mie (23 sites), S. (Gn.) bidentatum (22 sites) and S. (S.) suzukii (18 sites).
