TAXONOMIC AND ECOLOGICAL NOTES ON SIMULIUM (GOMPHOSTILBIA) PALAUENSE (DIPTERA : SIMULIIDAE) FROM PALAU, MICRONESIA, WITH REDESCRIPTIONS OF ADULTS AND DESCRIPTIONS OF THE PUPA AND MATURE LARVA

Redescriptions for the female and male, and descriptions for the pupa and mature larva, of Simulium (Gomphostilbia) palauense Stone are given based on reared adults and immature stages recently collected from Palau, Micronesia. S. palauense has several remarkable pupal and larval characters, which have not (or very rarely) been found in any other species of the subgenus Gomphostilbia, such as, in the pupa, the reduced number (i.e., four) of the gill filaments and the absence of spine-combs on the abdomen; in the larva, the presence of serrations on the lateral margins of the hypostomium, supernumerary mandibular serrations, and accessory sclerites, and the absence of a postgenal cleft. Ecological notes on immature stages are also given.