Amphinemura baisensis, Mo & Wang & Yang & Li, 2019

Mo, Raorao, Wang, Guoquan, Yang, Ding & Li, Weihai, 2019, A new species of Amphinemura (Plecoptera: Nemouridae) from Guangxi Zhuang Autonomous Region of southern China, Zootaxa 4585 (3), pp. 591-600 : 591-592

Amphinemura baisensis sp. nov.

( Figs. 1–6 )

Male habitus ( Fig. 1a ). Head brown with distinctive pattern; antennae and compound eyes dark brown; head wider than pronotum; pronotum brown, corners obtuse, subquadrate with two L-shaped and two C-shaped distinct dark brown markings anteriorly and posteriorly, respectively; legs dark brown. Wing membranes subhyaline, veins dark brown. Abdominal segments brown with dark brown terminalia.

Male ( Figs. 1–4 ). Forewing length 9.0– 10.1 mm, hind wing length 7.0– 8.6 mm. Tergum IX sclerotized, slightly concaved at anterior margin, with a large emargination posteromedially and with two paramedial groups of spinules and hairs present along mid-posterior margin ( Figs. 3a & 4a ). Slender vesicle of sternum IX claviform, length 5X width, ventral surface mostly membranous ( Figs. 3b & 4b ). Hypoproct trapezoidal in basal half, gradually narrowing toward tip but abruptly tapering subapically, and forming an apical nipple, bearing a process at the apex in lateral view; ventral surface mostly covered by long hairs ( Figs. 3 b–3c, 4b). Tergum X darkly sclerotized, a membranous concavity present below the epiproct, with a pair of lateral triangular processes. Cercus slightly sclerotized and weakly curved inward, nearly as long as 2.5X width. Epiproct ( Figs. 1 b–1f, 3a, 3d–3h, 4a, 4c–4d) mushroom-shaped with double hooked process at tip, dorsally mostly membranous and strongly scaled, bearing a longitudinal sclerotized strap laterally; two pairs of rounded lobes projecting in opposite directions, lobes anteriorly bearing rows of tiny spines along anterolateral margin overlapping the posterior lobes which project near the middle of the epiproct, distally curved backward. Ventral sclerite strongly sclerotized, narrow at base and then expended into a large triangular structure in the apical half, and with a semicircular ridge in lateral view, bearing many short, black spines ventrolaterally; abruptly tapering toward tip, that is inserted into dorsal sclerite between folds of dorsal sclerite, strongly curved downward in lateral view, and bifurcate into slender projections ( Figs. 3 c– 3d, 3f– 3g). Paraproct trilobed ( Figs. 2 , 3 a–3d, 4a–4b, 4e): inner lobe sclerotized and triangular, base partly hidden by hypoproct; median lobe mostly sclerotized and constricted at subapical, curved outward apically to form a small darkly sclerotized hook with several tiny black ventral spine ( Figs. 2 a–2e, 4a–4b, 4e); outer lobe slender and heavily sclerotized along outer margin, distinctly curved outward apically as a hook with 3 tiny spines at tip ( Figs. 2 b–2d, 2f, 4e).

Female ( Figs. 5–6 ). Forewing length 10.4–10.8 mm, hind wing length 8.2–9.2 mm. Sternum VII with sclerotized semicircular pregenital plate, posterior margin widely rounded, covering ¼ width of sternum VII and slightly overlapping anterior of sternum VIII. Sternum VIII forms butterfly-shaped subgenital plate sclerotized and slightly constricted at mid-lateral margin with a posteromedial notch, rectangular in ventral view and narrowinverted funnel in posterior view. Paragenital plates as a pair of subtriangular membranous lobes set at posterolateral side of subgenital plate. Sternum IX with anterior margin protruded medially with an incurved trapezoidal anterior plate in ventral view, posterior margin nearly truncate ( Fig. 5a ). Inner sclerites ( Figs. 5b , 6b, 6 d–6e) appearing as a tooth-shaped membrane, originating from under the subgenital plate, consisting of a pouch and a pair of rods; pouch nearly quadrate, corners bluntly round with a moderately sclerotized tube at tip except medial margin slightly sclerotized, bearing a bowknot-shaped structure at anterior top view with a pair of sclerotized tubes along lateral margins. Rods of inner sclerites connected at basal half, and distinctly swollen in lateral view, with a pair of subtriangular structure under paragenital plates.

Type Material. Holotype male ( HIST), CHINA: Guangxi Zhuang Autonomous Region, Baise County, Mt. Cenwanglaoshan , Dalongping , 1300 m, N 24°21' E 106°15', 2013. VII. 28, light trap, Mengchao Tan . Paratypes: 18 ♂, 6 ♀ ( HIST), light trap, same locality and date as holotype ; 2 ♂ ( CAU), light trap, Feiyang Liang, same locality and date as holotype .

Etymology. The new species is named after its type locality, Baise County, Guangxi Zhuang Autonomous Region, China.

Distribution. China (Guangxi Zhuang Autonomous Region)

Remarks. Amphinemura baisensis is apparently most similar to A. cordiformis Li & Yang, 2006 described from Guizhou Province of southwestern China, especially in respect in the dorsal and lateral aspects of the long and narrow epiproct and median lobes of the paraprocts forming a large hook with several tiny black spines, and particularly the epiproct with a cordiform projection at apical half and a long median projection. However, the new species may be easily separated from A. cordiformis by the epiproct bearing two projections curved in the opposite directions. The upper projection has rows of tiny spines along the anterolateral margin. The median projection of the epiproct of A. baisensis is bifurcate and strongly curved downward in lateral view and the median and outer lobes of paraprocts are approximately equal in length. In A. cordiformis , the epiproct has a cordiform projection and a pair of longitudinal straps paralleling the dorsal sclerite, and the median projection is not bifurcate and does not curve downward apically. Additionally, the median lobes of paraprocts are longer than outer lobes of paraprocts (figs. 1–5 in Li & Yang 2006). A similar cordiform projection of dorsal sclerite occurs also in A. gressitti Kawai, 1969 from Vietnam, but it is easily separated from the new species by the longer median projection of epiproct slightly curved upwards in lateral view (figs. 13, 15 in Stark & Sivec 2010).

Figures

FIGURE 1. Amphinemura baisensis sp. nov. (male). a. Adult habitus, dorsal view. b–c. Epiproct, dorsal view. d. Epiproct apex, ventral view. e. Epiproct, lateral view. f. Epiproct apex, anterolateral view.

FIGURE 2. Amphinemura baisensis sp. nov. (male). a. Left paraproct, ventral view. b. Median and outer lobes of left paraproct, lateral view. c. Median lobe of left paraproct, caudal view. d. Left paraproct, caudal view. e. Apex of the median left paraproct lobe, caudal view. f. Apex of the outer left paraproct lobe, caudal view.

FIGURE 3. Amphinemura baisensis sp. nov. (male). a. Terminalia, dorsal view. b. Terminalia, ventral view. c. Terminalia, lateral view. d. Epiproct, posterior view. e. Epiproct apex, dorsal view. f. Tip of epiproct, dorsal view. g. Tip of epiproct, dorsolateral view. h. Spines of left portion of apex of epiproct, dorsal view.

FIGURE 4. Amphinemura baisensis sp. nov. (male). a. Terminalia, dorsal view. b. Terminalia, ventral view. c. Epiproct, dorsal view. d. Epiproct, lateral view. e. Left paraproct, ventral view.

FIGURE 5. Amphinemura baisensis sp. nov. (female). a. Terminalia, ventral view. b. Vaginal complex, cleared, dorsal view. P, pouch; R, rod; S, subtriangular structure under paragenital plates; T, tube.

FIGURE 6. Amphinemura baisensis sp. nov. (female). a. Genital sclerites, ventral view. b. Vaginal complex, cleared, dorsal view. c. Vaginal complex, posterior view. d. Vaginal complex, lateral view. e. Vaginal complex, anterior top view. P, pouch; R, rod; S, subtriangular structure under paragenital plates; T, tube.