沖繩本島北部の山脚, 森林地帯で採集した蚊について

抄録

In order to know the mosquito fauna and biology in the forest area in the northern part of Okinawajima, Ryukyu Islands, Japan, a mosquito survey was conducted monthly for 6 years from 1976 to 1981. Collections were made mainly at a seaside cemetery (area H), foot of a mountain (area YS and YE) and a jungle forest (area AD). Adult mosquitoes were collected by daytime human-bait catches and larvae were also collected by a dipper and pipet from their natural habitats and at artificial containers such as wooden box, earthen jar, tin can and glass vial which had been placed beforehand. In total, 31 species of 11 genera were found in the present survey. Among them Ae. japonicus was a newly recorded species in Okinawajima. Larvae of Ur. nivipleura were also newly recorded in Japan. Toxorhynchites sp. is very similar to Tx. towadensis, belonging to the Tx. manicatus group. This species was very rare but its larvae were collected from wooden boxes placed in the jungle forest. The overwintering of the species was made in the larval stage. The larvae of Cx. ryukyensis, Ae. albopictus and Ur. n. ryukyuana were commonly found in area H. Most of the females collected in this area were Ae. albopictus (95%) and a few Ar. subalbatus (4%) was also included. At the base of the mountain, the larvae of Ae. albopictus, Ae. f. downsi, Ae. riversi, Ae. a. okinawanus and Or. anopheloides were predominant. In the YS area, teh predominant females were Ae. albopictus (60%) and Ar. subalbatus (38%). In the YE area, Ae. albopictus (40%), An. saperoi (31%) and Ae. riversi (15%) were predominant and the rest were Ar. subalbatus, Ae. a. okinawanus and Ae. f. downsi in decreasing order. In the jungle forest area (AD), the predominant species breeding in the artificial containers were the same as those in areas YS and YE except Ae. albopictus which was never collected in this area. The most common species that came to bite in the area was An. saperoi (62%) and its immature stages were commonly found in streams. Considerable numbers of Ae. a. okinawanus (25%) and Ae. riversi (8%) also came to bite in this area. Engorged females and/or larvae in all instars and pupae of Ae. albopictus, Ae. riversi, An. saperoi, Ae. a. okinawanus, Ar. subalbatus, Cx. ryukyensis and Ur. n. ryukyuana were collected even in winter. Apparently blood feeding, oviposition and adult emergence of these species continued in the winter season.