Studies on the ecology of blackflies (Diptera : Simuliidae) : 24. Fauna of the blackflies in Nagasaki Prefecture in winter

Abstract

The fauna and distribution of the blackflies in Nagasaki Prefecture were investigated from collections of larval and pupal stages of blackflies from streams in 30 localities in February 1993. A total number of 5,025 blackflies, 4,377 larvae (87.1%) and 648 pupae (12.9%) were collected at 30 sites. Those blackflies were classified into one genus and 13 species but one of them was unidentified. Three species, Simulium (Nevermannia) subcostatum, S. (E.) sp. H and S. (Simulium) suzukii were newly recorded from Nagasaki Prefecture. The predominant species was S. (S.) arakawae (44.6% in total number), followed by S. (N.) uchidai (28.6%), S. (Odagmia) aokii (11.8%) and S. (Gnus) bidentatum (7.3%). The most widely distributed species was S. (N.) uchidai (26 sites), followed by S. (S.) arakawae (21 sites), S. (Gn.) bidentatum (12 sites) and S. (S.) japonicum (8 sites). The species most widely distributed from lowland to highland areas were S. (N.) uchidai, followed by S. (S.) arakawae, S. (Gn.) bidentatum, S. (S.) japonicum, S. (O.) aokii and S. (S.) rufibasis.