Simulium (Gomphostilbia) asakoae Takaoka & Davies, 1995

Simulium (Gomphostilbia) asakoae Takaoka & Davies, 1995: 55 –60 (Female, male, pupa and larva); Takaoka et al. 2014b: 743.

Specimens examined. One female reared from a pupa, collected from a moderately to fastly flowing stream (width 1–3 m, depth 0.5–1.0 m, water temperature 17˚C, partially shaded, altitude 628 m, 16˚18’16.209” N/ 107˚12’48.027” E), Thua Thien Hue Province, central Vietnam, 24-II-2014, by H. Takaoka, M. Sofian-Azirun, Z. Ya’cob, C.D. Chen & K.W. Lau; one pupal exuviae collected from a small shallow stream (width 2–4 m, water temperature 17.0˚C, exposed to the sun, altitude 1,415 m) (12˚01’49.981” N/108˚21’51.175” E) slowly flowing in open land, Suoi Vang, Lac Duong, Lam Dong Province, southern Vietnam, 24-IV-2014, by H. Takaoka, M. Sofian- Azirun, Z. Ya’cob, C.D. Chen & K.W. Lau.

Distribution. Peninsular Malaysia, Thailand, Hong Kong, and Vietnam.

Remarks. This species is characterized in the female by the medium-long sensory vesicle, mandible with both inner and outer teeth, tuft hair on the base of the radial vein yellow, hind tibia yellowish on the basal two-thirds; in the male by the vermilion upper-eye facets in 11 vertical columns and 13 horizontal rows, hind tibia yellowish on the basal half, and hind basitarsus yellowish on the basal half; and in the pupa by the dorsal surface of abdominal segments 1 and 2 darkened (Takaoka and Davies 1995; Takaoka et al. 2013a). Females of S. (G.) asakoae were reported to bite humans (Choochote et al. 2005) and to serve as a vector of unknown filarial species in Thailand (Fukuda et al. 2003; Ishii et al. 2008).