Discovery of the Larvae and Pupae of the Black Fly () and Breeding Habitats of Potential Pest Species of the . (.) Subgroup (Simuliidae).

Two species of black flies (Simuliidae) in Thailand, Takaoka and Kuvangkadilok, 2000, and Takaoka, Srisuka & Saeung, 2022, are potent vectors of avian blood protozoa of the genera and and are pests of domestic avian species. Although the adults are abundant throughout Thailand, information on their breeding habitats is limited, and the immature stages of are unknown. We collected the larvae and pupae of from the Mekong River, the first-ever record of Simuliidae from this large continental river. Mitochondrial cytochrome c oxidase I and internal transcribed spacer 2 were used to associate the larvae and pupae with known adults. Both genetic markers strongly supported their identity as . The larvae and pupa of are described. The pupal gill filaments, larval abdominal protuberances, and setae distinguish this species from other members of the species group. The immature stages of inhabit a wide variety of flowing waters, from small streams (3 m wide) to enormous continental rivers (400 m wide); thus, is a habitat generalist. In contrast, was found only in the large Mekong River and is, therefore, a habitat specialist. Both species can exploit their principal habitats and produce abundant adult populations.