A new species of Haploperla from China (Plecoptera, Chloroperlidae)

Abstract A new species of the genus Haploperla, Haploperla triangulata sp. n., is described and illustrated from specimens collected in Qinghai province, China. Haploperla triangulata is characterized by the epiproct mostly sclerotized and hairless, sub-triangular in dorsal view and blunt at tip; and by the aedeagus with two median elliptical lobes ventrally. The new species is compared with its most similar congeners, and diagnostic characters are presented.


Introduction
The genus Haploperla Navás 1934 is mainly distributed in eastern Palaearctic and Nearctic regions, with only thirteen extant species reported (DeWalt et al. 2015). Only four Chinese species of Haploperla have been recorded from China, Haploperla ussurica Navás, 1934; H. lepnevae Zhiltzova & Zwick, 1971; H. valentinae Stark & Sivec, 2009;and H. choui Li & Yao, 2013(Navás 1934, Zhiltzova and Zwick 1971, Stark and Sivec 2009, Li et al. 2013. Unknown specimens of Haploperla from Shuixia, Huangzhong county in Qinghai province were collected in August 2015, and identified as a new species. The types are deposited in the Insect Collection of Yangzhou University, Jiangsu. The species described in this contribution increases the number of known Chinese Haploperla taxa to five.

Materials and methods
All type specimens are preserved in 75% or 100% ethanol. Specimens were examined and illustrated using a Leica stereomicroscope-MZAPO. Images were taken using a Leica SZ45. The holotype of the new species is deposited in the Insect Collection of Yangzhou University, China. Diagnosis. This species is characterized by a pale head, a pale pronotum disc with median stripe and brown margins, and the abdominal terga 1-8 with a longitudinal stripe. Epiproct mostly sclerotized and hairless, sub-triangular in dorsal view with a blunt tip. Aedeagus ventrally with two median situated elliptical lobes.

Haploperla triangulata
This new species is most similar to H. valentinae Stark & Sivec, 2009, known from Sichuan Province, China, but differs in the formation of the epiproct, which is mostly sclerotized and hairless in H. triangulata sp. n., whereas it is with sclerotized margins, membranous posterodorsal area and sparse patch of setae in H. valentinae (see Figs 13 and 17 in Stark and Sivec 2009). Besides, the subgenital plate of female is originating from tergum 8 to the posterior margin of tergum 9 in H. triangulata, while it's slightly produced as a small rounded lobe with long setae in H. valentinae (see fig. 15 in Stark and Sivec 2009). The details of the wing venation and aedeagus are not described for H. valentinae.
Adult habitus. Triocellate. General color light yellow patterned with dark brown. Head mostly pale yellow without any markings; compound eyes and ocelli black (Fig.  1). Pronotum hyaline, with median stripe and brown margins; meso-and metanota with dark brown W-shaped markings. Wings hyaline; Rs of both wings branched; A 3 of forewing fused with A 2 near base; anal field of hindwing small and folded with three  veins (Fig. 8). Coxae, tibiae and femura pale, tarsi brown. Abdominal terga 1-8 with a medial wide stripe. Cerci yellowish-brown with long brown setae (Figs 9, 10).
Etymology. The species epithet refers to the sub-triangular shape of the epiproct. Distribution. China (Qinghai province). Remarks. We describe a new species of the genus Haploperla, thereby increasing the total number of Haploperla species recorded in China to five. More Haploperla species are expected to be found in China in the future because the geographical conditions ensure suitable resources for stoneflies. More studies are needed to enrich our understanding of Haploperla.