Haploperla zwicki sp. n.

(Figs. 18-21)

Material examined. Holotype ♂ and paratype ♀ from Thailand, Doi Inthanon National Park, 2100 m, 6 April 1993, I. Sivec, B. Horvat (PMSL).

Adult habitus. General color pale yellow in life with obscure brown pattern on head, pronotum (Fig. 18) and abdominal terga. Wings and legs pale.

Male. Forewing length 5.5 mm. Abdominal tergum 9 produced over base of tergum 10. Epiproct a small, acute, triangular tab (Figs. 19-20). Aedeagus armed with a pair of slender rods, expanded apically and fused basally.

Female. Forewing length 6.5 mm. Subgenital plate a small, broadly rounded to triangular, median projection on abdominal sternum 8 (Fig. 21).

Larva. Unknown.

Etymology. The patronym honors our friend and colleague, Professor Dr. Peter Zwick, in recognition of his important synonymy of Hastaperla with Haploperla (Zwick 1977) .

Diagnosis and Discussion. This species is generally similar to H. longicauda Zwick (1977), known from Bhutan, but the epiproct of that species is more rounded, the aedeagal sclerites are not expanded apically, and the female subgenital plate is broader. The aedeagal rods of this species appear to be fused basally which is a feature not reported in other chloroperlid groups (Surdick 1985; Zwick 1967).