Amphinemura bifascia, Mo & Wang & Yang & Li, 2020

Mo, Raorao, Wang, Guoquan, Yang, Ding & Li, Weihai, 2020, Two new species of Amphinemura (Plecoptera: Nemouridae) from Damingshan National Natural Reserve of Guangxi, China, Zootaxa 4751 (1), pp. 131-142 : 132-133

Amphinemura bifascia sp. nov.

( Figs. 1–4 )

Male habitus ( Fig. 1a ). Body color generally brown. Head and mouthparts brown; antennae light brown, and palpi paler; compound eyes black; head wider than pronotum; pronotum pale brown, corners right-angled, subquadrate with distinct brown markings; legs light brown. Wing membranes subhyaline, veins brown. Abdominal segments light brown with darker terminalia.

Male ( Figs. 1–2 , 3 a–3d). Forewing length 5.8–5.9 mm, hind wing length ca. 5.0 mm. Tergum IX sclerotized, slightly concaved at anterior margin, with a subtriangular mid-posterior incision, two paramedial groups of strong black spines and with fringe of short and long hairs ( Figs. 1b, 1d , 2a ). Slender vesicle of sternum IX claviform, length 3.5X maximum width, slightly constrict basally and subapically, with a slightly swollen tip ( Figs. 1 c–1d, 2b). Hypoproct subquadrate basally, gradually narrowing toward nipple-like tip with sever strong subapical spines ( Figs. 1 c–1d, 2b). Tergum X sclerotized, a membranous concavity present below the epiproct, bearing a few strong spines either side of the epiproct. Cercus slightly sclerotized and weakly curved inward, nearly as long as 2.5X width. Epiproct ( Figs. 1b, 1d , 2a, 2 c–2f) subrectangular, strongly constrict subapically with a pair of parallel bands in apical half. Dorsal sclerite mostly membranous, with two slender, darkly sclerotized lateral arms which bearing a few small denticles either side of the arms at subapical and with two membranous rounded tip; a pair of subrectangular sclerotized bands present on dorsal surface. Ventral sclerite distinctly sclerotized, broad at base, then tapering toward apex, apical portion inserted into the fold of dorsal sclerite, forming triangular ridge bearing rows of black spines ventrally from middle to near apex, among then front spines large than latter spines; the sclerite ending in an obvious, rounded tip forming the apex of the epiproct. Paraproct trilobed ( Figs. 1 b–1d, 2a–2b, 3a–3d): inner lobe sclerotized and triangular, base partly hidden by hypoproct; median lobe sclerotized, strongly curved upward subapically, with three to five black spines along its wide tip; outer lobe slender and heavily sclerotized, distinctly curved outward with one black long spine at tip.

Female ( Figs. 3 e–3f, 4). Forewing length 6.7–7.1 mm, hind wing length 5.5–6.3 mm. General pattern of females similar to males but global and local color darker. Sternum VII with slightly sclerotized semicircular pregenital plate, slightly overlapping anterior of sternum VIII. Sternum VIII forms a trapezoidal subgenital plate with a posteromedial notch and a pair of heavily sclerotized, rectangular area, distinctly swollen in lateral view and without funnel in posterior view. Paragenital plate large, subtriangular, indistinct. Inner sclerites ( Figs. 4 a–4d) appearing as an oval sclerotized lobe below pregenital plate with a subtriangular gap in the middle and with a short tube at tip; a tooth-shaped membranous rod except medial margin slightly sclerotized originating from under the lobe.

Type Material. Holotype male ( CAU), CHINA: Guangxi Zhuang Autonomous Region, Nanning City , Wuming County, Damingshan National Natural Reserve , 1230 m, N 23°30’, E 108°26’, 2013.V. 21, X.Y. Liu . Paratypes: 1 female ( HIST), same locality and date as holotype ; 2 females ( HIST), light trap, same locality, 2013.V.20 ; 1 male ( HIST), light trap, same locality, 2014.V.11 , S. Su; 5 males, 6 females ( HNHM), same locality, stream beneath Golden Turtle Waterfall , 1150m, N 23°30.373’, E 108°26.141’, 2015.III.21 , J. Kontschán, J.N. Li, S. Li, W.H. Li, D. Murányi, G.Q. Wang; 2 females ( HNHM), same locality, forest brook towards Lawn of Love , 1215m, N 23°30.792’, E 108°26.487’, 2015.III.22 , J. Kontschán, J.N. Li, S. Li, W.H. Li, D. Murányi, G.Q. Wang; 6 males 3 females and 4 larvae ( HNHM), same locality, inflow stream above Dragon Lake , 1225m, N 23°29.751’, E 108°26.242’, 2015. III.22 , J. Kontschán, J.N. Li, S. Li, W.H. Li, D. Murányi, G.Q. Wang.

Etymology. The name refers to a pair of ventral bands in the apical part of epiproct. Latin “bi-” means two, double, and “fascia” means band.

Distribution. China (Guangxi Zhuang Autonomous Region).

Remarks. The male of the new species seems related to several Himalayan species of the A. luteipes species group ( Aubert 1967) in regard to the structure of the epiproct and paraprocts, including A. elegans Zwick, 1980 , A. luteipes Kimmins, 1947 , A. pseudoluteipes Aubert, 1967 , and A. pulchra Zwick, 1977 . The two sclerotized bands of dorsal sclerite of epiproct distinguish A. bifascia from the males of the above species. The male of A. bifascia is also similar to males of A. ctenospina Li & Yang, 2008b from Yunnan Province of southwestern China and A. unihamata ( Wu, 1973) from Shaanxi Province in northwestern China and Sichuan Province in southwestern China, sharing a pair of sclerotized bands located at apical ½ of dorsal sclerite of epiproct, a triangular ridge on the ventral sclerite in lateral view, a triangular inner lobe of paraproct and the swollen apex of median lobe. However, males of A. bifascia are easily separated from males of these two species by the epiproct being strongly constricted subapically, the ventral bands of epiproct subrectangular and nearly parallel, the lateral arms of epiproct bearing few small subapical denticles either side of the arms with two membranous rounded tips, median lobe of paraproct with three black apical spines and outer lobe of paraproct with one black large spine at tip. In males of A. ctenospina and A. unihamata , the epiprocts are quadrangular without subapical incisions, the ends of ventral bands of epiproct are acute and outcurved, the lateral arms of epiproct are heavily sclerotized and lacking denticles. Additionally, in A. ctenospina , there are two darkly sclerotized bands along lateral margins of dorsal sclerite, the median lobe of paraproct has a row of long sharp apical spines, and the outer lobe of paraproct lacks an apical spine. In A. unihamata , apical spines of median lobe of paraproct are dense, shorter than new species; the outer lobe of paraproct bears a triangular sclerite with a lateral spine on outer margin, while outer lobe of paraproct of A. bifascia lacks a triangular sclerite with a spine at the tip.

Figures

FIGURE 1. Amphinemura bifascia sp. nov. (male). a. Head and pronotum, dorsal view. b. Terminalia, dorsal view. c. Terminalia, ventral view. d. Terminalia, lateral view.

FIGURE 2. Amphinemura bifascia sp. nov. (male). a. Terminalia, dorsal view. b. Terminalia, ventral view. c. Epiproct, dorsal view. d. Epiproct, dorsal view. e. Epiproct, lateral view. f. Epiproct, lateral view.

FIGURE 3. Amphinemura bifascia sp. nov. (a–d male, e–f female). a. Right paraproct, ventral view. b. Tip of median lobe of right paraproct, oblique caudal view. c. Tip of median lobe of right paraproct, caudal view. d. Tip of median lobe of right paraproct, dorsal view. e. Head and pronotum, dorsal view. f. Terminalia, ventral view.

FIGURE 4. Amphinemura bifascia sp. nov. (female). a. Terminalia, cleared, ventral view. b. Terminalia, cleared, ventral view. c. Vaginal complex, cleared, dorsal view. d. Vaginal complex, cleared, dorsal view. e. Subgenital plate, lateral view. f. Vaginal complex, posterior view.