Simulium (Gomphostilbia) sazalyi Takaoka

Takaoka, Hiroyuki, Ya’Cob, Zubaidah & Sofian-Azirun, Mohd, 2018, Classification, annotated list and keys for the black flies (Diptera: Simuliidae) of Peninsular Malaysia, Zootaxa 4498 (1), pp. 1-65 : 19

19. Simulium (Gomphostilbia) sazalyi Takaoka , Ya’cob & Low, 2018

Simulium (Gomphostilbia) parahiyangum : (not sensu Takaoka & Sigit, 1992: Takaoka & Davies, 1995: 50–51.

Simulium (Gomphostilbia) sazalyi Takaoka , Ya’cob & Low, in Takaoka et al., 2018a: (Female, male, pupa and larva).

This new species was first recorded from Peninsular Malaysia as S. (G.) parahiyangum Takaoka & Sigit originally described from Java ( Takaoka and Sigit, 1992), based on the female, pupa and larvae collected from Gombak, Fraser’s Hill and elsewhere (Takaoka and Davies, 1995). Takaoka et al. (2018a) described this species as a new species, S. (G.) sazalyi , based on the smaller number of male upper-eye facets in 12–14 vertical columns and 13–15 horizontal rows (17 vertical columns and 15 horizontal rows in S. (G.) parahiyangum ) and pupal frons sparsely covered with tubercles (densely covered with tubercles in S. (G.) parahiyangum ).

This species is similar to S. (G.) dentistylum in having the flat ventral plate in the male, gill with eight short filaments, and antennal sheath with tubercles in the pupa, and deep postgenal cleft and deep constriction between abdominal segments 4 and 5 in the larva. However, it is distinguished from the latter species by the style lacking an apical spine in the male, antennal sheath with nine ridges with tubercles (ten ridges with tubercles in S. (G.) dentistylum ), and dorsal protuberances on abdominal segments 1–5 (such protuberances are absent in S. (G.) dentistylum ).

The pupae and larvae of this species are found in small to medium streams at low to medium elevations in many localities in Peninsular Malaysia.