Haploperla tuanjiena Du & Chen 2016

Material examined: We re-checked and redescribed the type material of Chen & Du (2016b). The type locality is Sichuan Province, Kangding, Xinduqiao, N 30.0738, E 101.8313, 3461 m (Fig. 9).

Male: Body length 5.5–6.0 mm, forewing length 6.0– 6.5 mm, hindwing length 5.5–6.0 mm (n = 5). Medium-sized Haploperla. Triocellate, Body color is pale yellow; head yellowish and intraocellar area light brown; compound eyes dark black. Pronotum yellow, posteriorly and anteriorly with a brown stripe on a disc (Fig. 6A). Tergum 9 posterior margins were slightly plump and covered with hairs. Tergum 10 divided, median portion forming a triangular structure to the base of epiproct. Epiproct subtriangular in dorsal view, inflated in lateral view, and anterolateral margin strongly sclerotized; posterodorsal area membranous; apex of epiproct sharp (Fig. 6B–D). Aedeagus enlarged, membranous rounded, dorsally covered with scattered small spines, ventrolaterally with a pair of sclerotized stylus and with a patch of sclerotized spines, the patch of spines in ventral view look like ear-shape on both sides (Fig. 7A–D).

Female: Body length 7.0 mm, forewing length 7.5 mm, hindwing length 6.0 mm (n = 1). Head, pronotum disk, body color and pattern similar to males (Fig. 8A). Terga 1–8 dorsally with large oval, brownish spots medially (Fig. 8B). The small subgenital plate originating from tergum 8, the posterior margins are bluntly rounded (Fig. 8C–D).

Remarks: According to Chen & Du (2016b), this species is closely related to H. maritima Zhiltzova & Levanidova, 1978, known from the Russian Far East and H. longicauda Zwick, 1977 from Bhutan. Herein, we add that this species is also close to H. choui Li & Yao, 2013 reported from Shaanxi, Qinling Mountains. The head and pronotum of H. choui are darkly pigmented (see Li et al. 2013: figs. 3, 4), which is different from H. tuanjiena, but the epiproct and aedeagus are close to H. tuanjiena. The aedeagus of H. choui is also with a pair of stylus ventrolaterally, but a band of dense setae is present in the dorsal aspect. This band of dense setae is not present in H. tuanjiena; the head and pronotum are also not darkly pigmented (Figs. 6A–D, 7A–D), which easily differentiates these species. In the original description of Chen & Du (2016b), the plates are not obvious, especially with regards to the epiproct and which may lead to misidentification in the future. The dorsal scattered spines on aedeagus and obvious lateral scales are absent (see Chen & Du, 2016b: figs. 4–6). Therefore, we redescribed and gave good quality plates of epiproct and aedeagus with complete morphological characters and descriptions to avoid confusion in the future.