Simulium weji Takaoka, 2001

Tangkawanit, Ubon, Kuvangkadilok, Chaliow, Baimai, Visut & Adler, Peter H., 2009, Morphotaxonomy of the Simulium (Simulium) tuberosum species group (Diptera: Simuliidae) in Thailand, Zootaxa 2048, pp. 31-46 : 39

Simulium weji Takaoka, 2001

Simulium weji differs from other species in the Thai tuberosum group by having pupae with microtubercles on the antennal sheath, conical cephalic microtubercles ( Fig. 4 D), gill filaments decreasing in length from dorsal to ventral, the dorsal filament thicker than the others, and the upper pair on a short stalk but the middle and lower pairs almost sessile ( Fig. 7 G). In the female, sternite VII has a pair of long clusters of hairs. In the male, the median sclerite is somewhat teardrop shaped ( Fig. 9 E) and the head is slightly wider than the thorax. Meristic characters of the larvae (e.g., number of primary fan rays, lobules on the rectal papilla, hooklet rows, and hooklets per row) are greater than those of all other Thai members of the S. tuberosum group (Table 2) and might be related to the unique calcareous stream habitat of S. weji . The cocoons of this species accumulate a deposit of calcium carbonate.

Figures

FIGURE 4. Cephalic plates of pupae of Simulium tuberosum group from Thailand, showing distribution of microtubercles. A, S. doipuiense cytoform A (male). B, S. rufibasis (male). C, S. setsukoae (female). D, S. weji (female). E, S. yuphae (female). Scale bars = 0.1 mm.

FIGURE 7. Gill filaments of Simulium tuberosum group from Thailand. A, S. doipuiense cytoform A. B, S. manooni. C, S. rufibasis. D, S. setsukoae. E, S. tani cytoform F. F, S. tani cytoform H. G, S. weji. H, S. yuphae. Arrow indicates pit-like organ.

FIGURE 9. Median sclerites of males of Simulium tuberosum group from Thailand. A, S. doipuiense cytoform A. B, S. rufibasis. C, S. setsukoae. D, S. tani complex. E, S. weji. F, S. yuphae. Scale bars = 0.05 mm.