Capnia trispinosa Chen & Du, 2017

Chen, Zhi-Teng & Du, Yu-Zhou, 2017, New species and a new record of Capniidae (Plecoptera) from Xinjiang Uygur Autonomous Region of northwestern China, Zootaxa 4311 (1), pp. 122-128 : 123-124

Capnia trispinosa Chen & Du , sp. nov.

Figs. 1–6 .

Male. Body length 5.9–6.6 mm. Forewings length 5.4–5.9 mm, hindwings length 4.5–5.0 mm. Body generally brown. Head wider than pronotum, antennae dark brown; three ocelli pale, compound eyes dark ( Fig. 1 ). Pronotum subquadrate, corners obtuse. Wings macropterous, exceeding tip of abdomen, hyaline with brown veins; R vein of forewing curved at its divergence with Rs; anal field of hindwing small and folded with three veins. Tergal antecosta complete on terga 6–7, interrupted on other abdominal segments ( Fig. 1 ). Legs generally brown. Cercus slender and hairy, with each segment enlarged distally ( Fig. 1 ).

Male abdomen: Terga 5–10 with sclerotized anterior margins ( Figs. 1–2 ). Tergum 7 with a hump-like, darkly sclerotized posteromedial process, bearing sensilla basiconica ( Figs. 2–3 ). Tergum 8 strongly incised anteromedially, with posterior membranous area extending to base of epiproct. Terga 9–10 cleft and sclerotized with median membranous area. From dorsal aspect, main epiproct sclerite long triangular with a tongue-shaped apex; apical ¼ and basal ¼ with three large spines, the basal spine being the distal, upcurved end of the inner sclerite and the paired apical spines representing sclerotized portions of the eversible crest; two ridges elevated from near base of the paired anterior spines to posterolateral margins, median area with furrows; posterior margin with two dark sclerites, covered by long caudal setae ( Fig. 5 ). In lateral aspect, the lower portion of the main epiproct sclerite widened and rounded; apex of main epiproct sclerite blunt with arced ventral surface ( Fig. 6 ). Sternum 9 lacking a vesicle; subgenital plate spade-shaped with sclerotized margins; paraprocts unfused and elongated ( Fig. 4 ).

Female. Unknown.

Type material. Holotype: male, China: Xinjiang Uygur Autonomous Region, Fuyun County, Riverside Park, Eerqisi River , 793m, 46.9865 N, 89.5247 E, 16 April, 2017, Hai-Yang Xue ( ICYZU) . Paratype: 2 males, same locality and data as holotype ( ICYZU) .

Etymology. The specific epithet refers to the three dorsal spines of epiproct.

Remarks. The male genitalia of the new species is similar to the C. atra Morton, 1896 species group ( Zhiltzova 2001). Capnia trispinosa is most similar to C. ahngeri Koponen, 1949 (in: Koponen & Brinck 1949) from the Russian Far East, but can be distinguished by the three large dorsal spines of the main epiproct sclerite. In C. ahngeri , the main epiproct sclerite is much narrower with only two dorsal spines; tergum 9 is not completely divided; process on tergum 7 is much wider; shape of membranous areas on terga 6–10 is distinct from that of the new species (see figs. 1067–1069 in Teslenko & Zhiltzova 2009).

Figures

FIGURES 1 – 6. Capnia trispinosa, sp. nov. 1. Male habitus, dorsal view; 2. Male terminalia, dorsal view; 3. Male terminalia, lateral view; 4. Male terminalia, ventral view; 5. Male epiproct, dorsal view; 6. Male epiproct, lateral view.