Amphinemura bicolorata Li, Yang and Li 2024, sp. n.
Creators: name: Li, Meng-Yu
name: Yang, Ding
name: Li, Wei-Hai
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Plecoptera
Nemouridae
Amphinemura
Amphinemura bicolorata

description: Amphinemura bicolorata Li, Yang and Li, sp. n.
Type material
Holotype. 1♂, China, Xizang Autonomous Region, Chayu County, Yare, 2417 m, 28.670°N, 97.471°E, 13 June 2019, leg. Yang Qi-Cheng (CAU).
Paratypes. 4♂♂, 4♀♀, same data as the holotype.
Description
Adult habitus. Body colour dark brown. Head mostly black, with a brown band between posterior ocelli; compound eyes black; antennae brown, scape and pedicel black; palpi brownish; head wider than pronotum; pronotum nearly quadrate, with scattered rugosities, anterior corners rounded; legs: femora dark brown, tibia and tarsi brownish. Wing membranes subhyaline, veins brown to dark brown. Abdominal segments brown with darker terminalia.
Male. (Figures 1a–d, 2, 5a–d). Forewing length 6.8–8.2 mm, hindwing length 5.2–7.2 mm. Tergum IX (Figures 1a, 2a) sclerotised, but lateral area darker, with subtriangular anteromedial indentation, and with two paramedial groups of small spines and several long bristles present along posterior margin. Slender vesicle of sternum IX (Figure 1b) claviform, length 3.0× maximum width, basally and medially slightly constricted. Hypoproct subrectangular basally, medially slightly swollen and then gradually narrowing towards nipple-like tip. Tergum X (Figures 1a, 2a) darkly sclerotised, with a membranous concavity below the epiproct, two irregular rows of stout, small black spines on either side of the epiproct. Cercus (Figure 1a, b) slightly sclerotised laterally, short, cylindrical, weakly curved inward, about as long as 2.5× maximum width. Epiproct (Figures 1a, c, 2 a, c, d, 5a–c) subrectangular with rounded apex. Dorsal sclerite with a slender and slightly curved lateral arms ending before a radial row of short wrinkles along apex. Ventral sclerite dark and strongly sclerotised, located medially and narrow in dorsal view, slightly broad at base, tapering towards tip, ventrally enlarged into a wide triangular ridge with rows of tiny black spines.Paraproct (Figures 1b, d, 2b, 5d) trilobed: inner lobe sclerotised, nearly rectangular and moderately long; median lobe long and narrow, distinctly sclerotised, apex strongly curved upward and outward, with two rows of black spines in a curved arrangement, slightly swollen tip; outer lobe bicoloured, slender and darkly sclerotised at base, distal half pale and membranous, distinctly curved outward apically.
Female. (Figures 1e–f, 5e–f). Forewing length 8.0 mm, hindwing length 6.8 mm. Sternum VII (Figures 1e, 5e) produced in a large sclerotised pregenital plate, posterior margin widely rounded, covering anterior half of sternum VIII and inner slcerite. Sternum VIII (Figures 1e, 5e) forms sclerotised subquadrate subgenital plate with a small triangular posterior notch, posteromedial area pale and lightly sclerotised, contrasting the mostly dark brown plate. Paragenital plate (Figures 1e, 5e) paired, forming subquadrate brown lobes connected with posterolateral corner of subgenital plate and the lateral portion thickened ending in margin of the segment. Sternum IX (Figures 1e, 5e) weakly sclerotised, medially produced. Paraprocts wide triangular, with blunt tip; cerci short and brownish.
Inner genitalia (Figures 1f, 5f) in dorsal view, opening under the posteromedial notch of the subgenital plate, having a basal pouch, a pair of obliquely triangular anterolateral sclerites, the sclerite with bifurcate apex attached to the pouch, and the anterolateral sclerite of the subgenital plate; the pouch anteriorly ends in longitudinal tube-like sclerite directed into receptacle; a pair of round mesolateral sclerites located between anterolateral sclerites and anterolateral corners of subgenital plate.
Nymph
Unknown.
Etymology
The Latin specific epithet refers to the bicoloured outer lobe: ‘bi’ meaning two and ‘coloratus’ meaning coloured.
Remarks
The new species resembles A. exigua Zwick, 1977, a species described from Bhutan. The two species share a similar ventral sclerite of epiproct, and median lobe of paraproct that is armed with apical row of spines. However, A. bicolorata can be easily separated from A. exigua by narrower apex of dorsal sclerite of epiproct and by the outer lobe of paraproct which lacks apical spines. In A. exigua, the outer lobe of paraproct is fringed with a row of apical spines; dorsal sclerite of epiproct is expanded subapically (figs. 21–24 in Zwick 1977).
The female of A. bicolorata sp. n. is generally similar to A. pulchra Zwick, 1977 from Bhutan; distinction must rely on the size of subgenital plate and may be confirmed also by the examination of inner sclerite: in A. pulchra (fig. 37 in Zwick 1977), subgenital plate is much larger, covering nearly half width of sternum 8, and the inner sclerite lacks the distinct pair of anterolateral sclerites present in A. bicolorata sp. n.
description: Published as part of Li, Meng-Yu, Yang, Ding & Li, Wei-Hai, 2024, Two new species of Amphinemura (Plecoptera: Nemouridae) from south-western China, pp. 645-655 in Journal of Natural History 58 (17 - 20) on pages 646-649, DOI: 10.1080/00222933.2024.2354960, http://zenodo.org/record/13219599