Phanoperla wieng sp. n.

(Figs. 37-41)

Material examined. Holotype ♂ from Thailand, Phrae Province, Wieng Ko Sai National Park, Namtok Maekueng, Tier 1, 99° 35’ N, 17° 58’ E, 350 m, 25-26 October 2002, Chiang Mai University Team (PMSL).

Adult habitus. Biocellate with ocelli nearly touching. Occiput and most of frons pale but median suture dark and area around M-line dusky; lappets brown (Fig. 37). Palpi and antennae brown. Legs pale brown, dorsum of tibiae and tarsi darker. Wings brown with darker venation.

Male. Forewing length 10 mm. Tergum 8 without median lobe. Tergum 9 with lateral sensilla basiconica patches set on low mounds, median patch absent. Hemitergal processes short, wide at base and tapered to apex (Fig. 38). Aedeagal tube sclerite slender and narrowed apically; tube sprinkled with small spines over the apical region (Fig. 41); sac rather densely armed over most of surface; largest spines form a subapical double ring and an additional mesal circle, partially divided by a double row of spines (Figs. 39-41).

Female. Unknown.

Larva. Unknown.

Etymology. The species name, used as a noun in apposition, is based on the type locality.

Diagnosis. The male genitalia and aedeagus of this species is similar to those of P. vietnamensis Zwick. The new species differs in lacking the two small rows of sensilla which form the mesal patch on tergum 9 in P. vietnamensis, and in having a complete double row of large cultriform spines encircling the aedeagal sac.