Simulium siamense Takaoka and Suzuki 1984

Simulium siamense was described from specimens collected in Mae Hong Son, Thailand (Takaoka and Suzuki 1984). The present specimens differ slightly from those in the original description by having minute black setae on the larval thorax. The eightfilamented gill is arranged in groups of 3 + 3 + 2 from dorsal to ventral (Fig. 3 D). The larva can be identified by the presence of dark setae with 6–8 branches on abdominal segments V–VIII (Fig. 2 D).

The chromosomes of this species were described by Kuvangkadilok et al. (2003). Sixteen of 52 larvae were analyzed for major landmarks. None of the centromere regions are expanded. The IIS arm has the ring of Balbiani near the subterminal bulge (Fig. 1 E).