Sphaeronemoura acutispina, Mo & Wang & Yang & Li, 2020

Mo, Raorao, Wang, Guoquan, Yang, Ding & Li, Weihai, 2020, A new species of Sphaeronemoura (Plecoptera: Nemouridae) from Guangxi Zhuang Autonomous Region of southern China, Zootaxa 4763 (3), pp. 447-450 : 447-450

Sphaeronemoura acutispina sp. n.

( Figs. 1–2 )

S. hamistyla ( Wu, 1962) : Cao, Wang & Li, 2019: 293.

Male habitus ( Fig. 1a ): General color brown. Head dark brown, antenna brown; head slightly wider than pronotum. Pronotum lighter than head, rectangular, wider than long; surface rough with distinct rugosities and darker markings; corners right-angled. Legs brown; wings membrane brownish, venation dark brown.

Male ( Figs. 1–2 ): Forewing length of holotype ca. 10.8 mm. Tergum 8 weakly sclerotized, asymmetrically produced posteromedially forming a broad sclerotized subtrapezoidal plate. Tergum 9 weakly sclerotized, with a large, deep subtriangular posteromedial incision, bearing two sloping patches with several tiny spines and hairs paramedially. Sternum 9 with vesicle claviform, ca. 2X longer than widest, slightly constricted basally, mostly membranous; hypoproct subpentagonal, apical half distinctly tapering toward a nipple-like apex and covering with dark wrinkles ( Figs. 1c , 2b ). Tergum 10 distinctly sclerotized, with a longitudinal membranous area present below epiproct bearing scattered small spines located along lateral margin, and with a tergal projection located on each elevated midlateral margin. Cercus slightly sclerotized, longer than wide, slightly incurved, with oval process at tip. Epiproct subrectangular, flagellum with acute tip. Dorsal sclerite sclerotized laterally, concaved apically, bent downwards, delimiting a large, membranous dorsal area. Flagellum slender, hook-like: proximally curved right, and distally strongly curved to the left with an open apical loop; grooved medially; swollen apically, with a pointed apical spine. Ventral sclerite strongly sclerotized, subtriangular, slightly enlarged medially before inserted in dorsal sclerite, distinctly narrowing apically to form a long flagellum and bearing a row of small teeth along the ventral ridge. Paraprocts divided into three lobes: outer lobe, mostly membranous, distinctly sclerotized in inner margin forming a slender strip enlarged at its tip, bearing scattered hairs at membranous area; median lobe bilobed, mostly sclerotized, covered with several hairs at outer apical area, with a claviform strongly sclerotized inner projection and a membranous triangular outer projection; inner lobe triangular, strongly sclerotized, approximately equal in length with inner projection of paraproct.

Female: Unknown

Type material: Holotype male ( CAU): CHINA: Guangxi Zhuang Autonomous Region, Tianlin County, Cenwanglaoshan National Nature Reserve , Dalongping Protection Management Station , 1300 m, N 24°21', E 106°15', 2013.VII. 28, light trap, Yunlan Jiang.

Distribution: China (Guangxi Zhuang Autonomous Region). The holotype, the only specimen known, was collected at the Dalongping Protection Management Station in the Cenwanglaoshan National Nature Reserve. The reserve is located the east of Tianlin County of Guangxi, and is one of the ten water source forest nature reserves of the region.

Etymology: The specific name refers to the pointed apical spine of epiproct. Latin “acutus” means pointed, and “spina” means spine.

Remarks: The new species is similar to S. hamistyla described by Wu (1962) from Yunnan Province of southwestern China, sharing the shape of epiproct and the large asymmetrical plate of tergum 8. However, the male of S. acutispina may be separated from S. hamistyla by the median lobe of paraproct, and ventral spine and apical spine of epiproct. In S. hamistyla , median lobe has a slender apical sclerotized bulge without a membranous triangular outer projection and has a black, stout ventral spine, and no apical spine of epiproct ( Li & Yang 2009).

Figures

FIGURE 1. Sphaeronemoura acutispina sp. n. (male). a. Head and pronotum, dorsal view. b. Terminalia, dorsal view. c. Terminalia, ventral view. d. Right paraproct, caudal view. e. Right paraproct, caudal view.

FIGURE 2. Sphaeronemoura acutispina sp. n. (male). a. Terminalia, dorsal view. b. Terminalia, ventral view. c. Flagellum of epiproct, dorsal view. d. Epiproct, dorsal view. e. Epiproct, dorsal view. f. Epiproct and tergal projection of tergum 10, lateral view. g. Epiproct and tergal projection of tergum 10, lateral view. h. Basal half of epiproct, lateral view.