Capnia oblata Chen & Du

Chen, Zhi-Teng & Du, Yu-Zhou, 2017, Description of two new Capnia species (Plecoptera: Capniidae) from the Hengduan Mountains of southwestern China, Zootaxa 4273 (4), pp. 595-599 : 596

Capnia oblata Chen & Du , sp. nov.

Figs. 2–12 .

Male. Body length 5.8 mm. Forewings length 6.2 mm, hindwings length 4.8 mm. Body generally dark brown. Head nearly as wide as pronotum; three ocelli pale, compound eyes dark ( Figs. 2–3 ). Pronotum wider than long, corners obtuse. Wings macropterous, hyaline with brown veins; R vein of forewing curved at its divergence with Rs; anal field of hindwing small and folded with three veins ( Fig. 4 ). Tergal antecosta interrupted on terga 1–6, complete on terga 7–10 ( Fig. 2 ). Legs brownish to dark brown. Cercus slender and hairy, with distally enlarged segments ( Fig. 5 ).

Male abdomen: Terga 2–10 with sclerotized anterior margins ( Fig. 2 ). Tergum 9 strongly concave and sclerotized at anterior margin, posteromedially with an elevated, medially notched sclerotized process, the process connected with the anterior margin by a median bar ( Figs. 6–7 ). Tergum 10 cleft and sclerotized. Main epiproct sclerite long triangular-shaped in dorsal aspect, with complete dorsal division extending from the broad and dark base to the blunt and flattened tip; from lateral view, main epiproct sclerite slightly constricted and nearly parallelsided at basal ¼, then enlarged before the abruptly constricted apex ( Fig. 8 ). Sternum 9 with a rounded, hairy vesicle, the vesicle as long as wide, length is one third of the length of subgenital plate ( Fig. 9 ). Subgenital plate subtriangular with sclerotized lateral margins; paraprocts unfused and parallelogram-shaped ( Fig. 9 ).

Female. Body length 7.4 mm. Forewings length 7.5 mm, hindwings length 6.2 mm. General color similar to male except for the darker abdominal segments ( Figs. 10–11 ). Sternum 8 with a quadrate membranous area anteromedially; subgenital plate basally constricted with a wider rectangular apex, exceeding the lateral sclerites of sternum 8; the lateral sclerites subrectangular, with rounded posteromedial angles ( Fig. 12 ).

Type material. Holotype: male, China: Yunnan Province, Deqin County, Baima Snow Mountain , 4750m, - 26.4 °C (written by the collector, perhaps the air temperature), 23 Feb, 1987, Da-Rong Yang ( ICYZU). Paratype: 1 female, same locality and data as holotype.

Etymology. The specific epithet refers to the flattened apex of epiproct.

Remarks. The new species belongs to the C. cordata Kimmins, 1946 species group sensu Zhiltzova (2001). It seems most similar to C. cordata Kimmins, 1946 from Tibet, but can be distinguished by its apically flattened main epiproct sclerite, by posteromedial process of tergum 9 connecting antecosta with a medial sclerite bar, and by paraprocts unfused and parallelogram in shape. In C. cordata , apex of main epiproct sclerite is slender and hooked. In addition, the terminal segments of cerci are distally enlarged in the new species, however in C. cordata , these segments are filiform with uniform thickness (see fig. 9 in Kimmins 1946). Another member of the C. cordata species group, C. yunnana Li & Yang, 2011 , has been also reported from Baima Snow Mountain in Yunnan Province. However, in C. yunnana , the main epiproct sclerite of males has a swollen apex; posterior margin of subgenital plate in females is not flattened (see figs. 4, 7 in Li et al. 2011).

Figures

FIGURE 2 – 12. Capnia oblata, sp. nov. 2. Male habitus, dorsal view; 3. Male head and pronotum, dorsal view; 4. Right wings, dorsal view; 5. Cerci, dorsal view; 6. Male terminalia, dorsal view; 7. Apex of male epiproct, dorsolateral view; 8. Male terminalia, lateral view; 9. Male terminalia, ventral view; 10. Female habitus, dorsal view; 11. Female head and pronotum, dorsal view; 12. Female terminalia, ventral view.