抄録
The geographical distributions of the genus Simulium Latreille s.l. in the Oriental and Australasian Regions were mapped. The patterns of distribution were examined at the subgenus and species-group levels. Among the 11 subgenera recorded in these regions, five (Byssodon, Eusimulium, Montisimulium, Nevermannia and Simulium s.str.) were essentially Palaearctic, apparently penetrating to varying extents from the north to the Oriental Region and two of which were further extending their eastward ranges up to the Australasian Region; while the other six subgenera (Gomphostilbia, Hebridosimulium, Himalayum, Inseliellum, Morops and Wallacellum) were nearly endemic to the Oriental or Australasian Regions or both. All the endemic subgenera, except Himalayum, had their own center of development and distribution on the islands. Eight of 12 species-groups of Simulium s.str. were mostly confined to the Oriental Region, and five of which demonstrated a definite insular pattern in their distribution. The probable dispersal routes were inferred for several species-groups of the subgenera Nevermannia and Simulium s.str. The Simulium faunae of the Philippines, Sulawesi and the Maluku Islands present a mixture of the Oriental and Australasian elements but the faunal break is likely to be seen on both sides of the Weber's Line.
