The males of Simulium (Gomphostilbia) miblosi Takaoka in the S. epistum species-group, and S. (G.) apoense Takaoka in the S. ceylonicum species-group, both from Mindanao, the Philippines, are described for the first time. The male of S. (G.) miblosi is characterized by the hind tibia yellowish white on the basal three-fifths, elongate calcipala 1.5 times as long as its basal width, and ventral plate triangular ventrally (0.74 times as high as its greatest width) when viewed caudally. Tubercles on the frons and trichomes on the head and thorax of the pupa of this species are illustrated for the first time. The male of S. (G.) apoense is characterized by the small sensory vesicle 0.16–0.19 times as long as the third palpal segment, and enlarged hind basitarsus 1.0 and 1.2–1.3 times as wide as the hind tibia and femur, respectively. Taxonomic notes of these two species relevant to related species in each species-group are given.

Simulium (Wallacellum) tuyense Takaoka, one of the 14 Philippine species in the subgenus Wallacellum Takaoka, is a rare species in having the pupal antennal sheath with a row of stout spines on the apex of each protuberance corresponding to flagellomeres 2–9. The female of this species is described for the first time based on specimens from Mindoro, the Philippines. It is characterized by an elongate sensory vesicle, triangular ovipositor valve, genital fork with two projections, and paraproct not produced anteriorly. This species is morphologically indistinguishable in the female, as in the male and pupa, from S. (W.) yonakuniense Takaoka from Yonakuni Island, Japan and Lanyu Island, Taiwan. Taxonomic notes on the female of this species relevant to those of related species are provided. Collection data to validate earlier distribution records of S. (W.) tuyense and S. (W.) suyoense Takaoka from Mindanao are presented.