Capnia zijinshana Du & Chen, 2016

Chen, Zhi-Teng, 2020, Plecoptera larvae of China: larval descriptions of two stonefly species (Capniidae, Nemouridae) from Jiangsu Province, Zootaxa 4759 (2), pp. 223-236 : 224-226

publication ID	https://doi.org/ 10.11646/zootaxa.4759.2.5
publication LSID	lsid:zoobank.org:pub:980645D8-8C4F-463F-8E51-07D7662C87BA
DOI	https://doi.org/10.5281/zenodo.3811449
persistent identifier	https://treatment.plazi.org/id/039F87E2-5651-4957-FF43-FC06FB6CF8FF
treatment provided by	Plazi
scientific name	Capnia zijinshana Du & Chen, 2016
status

Treatment

Capnia zijinshana Du & Chen, 2016 View in CoL

Figs. 2–10 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 View FIGURE 6 View FIGURE 7 View FIGURE 8 View FIGURE 9 View FIGURE 10 .

Capnia zijinshana Du & Chen, 2016 View in CoL . Zootaxa, 4170(1): 187; Chen & Song, 2019. Zootaxa, 4629(2): 238.

Material examined. Two male larvae and seven female larvae, China: Jiangsu Province, Nanjing City, Mt. Zijinshan ( Fig. 1 View FIGURE 1 ), 32°03′20″N, 118°51′15″E, 50m, Jan. 5, 2020, leg. Zhi-Teng Chen (ICJUST).

Mature larva. Body length 7.0–7.5 mm. General color pale brown, appendages pale ( Figs. 2 View FIGURE 2 , 3 View FIGURE 3 ). Head rounded, frontal area covered with pale, soft hairs; clypeus broad and elliptical, with a posterior notch; epicranial suture pale ( Figs. 4 View FIGURE 4 ). Three ocelli somewhat reddish; compound eyes dark and covered with pale, short hairs. Antennae slender, subequal to ⅔ of body length, each segment apically fringed with several short bristles ( Fig. 5 View FIGURE 5 ). Mouthparts typical euholognathan as in Fig. 4C View FIGURE 4 and Fig. 6 View FIGURE 6 , glossa and paraglossa of labium knob-shaped, subequal in length ( Fig. 4C View FIGURE 4 ); labial palp short, three-segmented with longest apical segment; maxillary palp five segmented ( Fig. 6A View FIGURE 6 ); stipes of maxilla long cylindrical, basal half covered with sparse long bristles; galea hook-shaped, outer margin of apical half fringed with several moderate spines, inner margin glabrous; lacinia semicircular and weakly sclerotized, with long, stout apical teeth, dorsal comb with about 20 long bristles, ventral comb with about 10 long bristles. Mandible with six major unserrated, sclerotized apical teeth, near the apical teeth with a marginal comb of about 13 moderate bristles ( Fig. 6 View FIGURE 6 B–D). Cervix elongated and membranous, ventrally with paired lateral cervical sclerites ( Fig. 4 View FIGURE 4 A–C). Thoracic terga covered with dense, pale hairs ( Fig. 4 View FIGURE 4 ). Pronotum subquadrate with obtuse corners ( Fig. 4A, B View FIGURE 4 ), anterior margin narrower than posterior margin and slightly protruded anterolaterally, lateral margins with long hairs; anterior half of pronotum with a curved transverse suture, pattern indistinct, with small dark brown spots together resembling the letter Х. Wing pads of meso- and metanota pale ( Fig. 4D, E View FIGURE 4 ), triangular with a rounded tip, margined with long bristles. Coxae membranous and glabrous dorsally, but ventrally and laterally with short spines; trochanters ventrally with short spines ( Figs. 4C, F View FIGURE 4 , 7 View FIGURE 7 ). Femora dorsally covered with sparse, short spines ( Fig. 7A, C View FIGURE 7 ), ventrally with two longitudinal rows of spines along the two ridges respectively near the outer and inner margins ( Fig. 7B, D View FIGURE 7 ). Tibiae evenly covered with short spines, inner and outer margins with long, thick spines; two large tibial spurs present ventrally ( Fig. 7B, D View FIGURE 7 ). Outer margin of femora and tibia covered with sparse swimming hairs, the length of which increases in the distal part ( Fig. 7B, D View FIGURE 7 ). Tarsal segments with sparse short spines on inner margins; mid tarsal segment shortest; basal tarsal segment two times longer than mid tarsal segment; apical tarsal segment longest, two times longer than basal tarsal segment; outer margins of tarsal segments with sparse swimming hairs ( Fig. 7B, D View FIGURE 7 ). Claws sharp, apically sclerotized ( Fig. 7 View FIGURE 7 ).

Abdominal segments covered with pale, short hairs; posterior margin of each tergum fringed with long bristles ( Fig. 8 View FIGURE 8 ); terga and sterna distinctly divided ( Fig. 9A, B View FIGURE 9 ); terga 1–9 generally dark brown; sterna 1–8 generally pale brown ( Figs. 8–9 View FIGURE 8 View FIGURE 9 ). In male larvae: tergum 10 projected backwards, forming a sharp, apically glabrous process ( Fig. 8C View FIGURE 8 ); a slender adult epiproct enclosed within the process; a rounded adult vesicle visible below sternum 9; paraprocts kidney-shaped in ventral view. In female larvae: abdominal segments wider than the male ( Fig. 3 View FIGURE 3 ); tergum 10 posteriorly rounded; paraprocts subtriangular in ventral view. Cerci pale, subequal in length to abdomen, each segment with several long apical bristles, length of which does not exceed the segment length ( Figs.1 View FIGURE 1 , 10A, B View FIGURE 10 ).

Remarks. Capnia zijinshana is the only known capniid species from southeastern China, being restricted to one small stream in Mt. Zijinshan ( Du & Chen 2016, Chen & Song 2019). The larvae are similar to the adults, exhibiting hairy body segments and appendages. Both sexes of the larvae are easily separated by the body shape and terminal modifications. In early January no adults of C. zijinshana were collected near the nearly dry stream. Larvae were collected from the fallen leaves in the water and crawled actively when captured by dip net ( Fig. 1 View FIGURE 1 ).