Metrocoris zhengi Chen & Bu, 2016, sp. nov.
Creators: name: Chen, Zhen Ye Ping-Ping
name: Bu, Wen-Jun
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Gerridae
Metrocoris
Metrocoris zhengi

description: Metrocoris zhengi sp. nov.
(Figs. 20, 28, 33, 38, 43, 48, 53, 58, 66, 71, 81–84)
Material examined. Holotype: apterous male, CHINA, Guizhou Prov., Zunyi city, Daozhen county, Dashahe Nature Reserve, Mopanshi (29°01'N, 107°41'E), 10 August 2013, 1100 m, leg. Zhen Ye (NKUM). Paratypes: 1 apterous male and 1 apterous female (NCTN), 1 apterous male and 1 apterous female (NKUM), same data as holotype.
Diagnosis. The fore femur only with a subapical indentation and a small single apical tooth (Fig. 43); the unmodified inner surface of the fore tibiae (Fig. 43); the relatively large male abdominal segment VIII and pygophore (Figs. 48, 53); the proctiger laterally raised and with a pair of blackish dots (Fig. 58); the typically triangular shape of the paramere blade (Figs. 66, 83); accessory lateral sclerites of endosoma relatively thick in dorsal view (Figs. 71, 81); female abdominal sternum VII laterally constricted, apical half forming a relatively broad lobe, caudal margin without median notch (Fig. 38), are the diagnostic features of M. zhengi sp. nov..
Description. Apterous male (Figs. 20, 28). Body length 6.62–6.71, body width (across acetabula) 3.08–3.21. Colour: dorsal yellow with prominent black stripes; interocular dark mark usually arrowhead shaped, bifid posteriorly, along inner margin of eyes without narrow dark line; first antennal segment yellowish brown, remaining segments usually blackish; rostrum yellowish with black apex; pronotum with T-shaped black stripe, lateral pronotal stripe very broad; mesonotum with median slender longitudinally stripe, sublateral stripes broader than lateral stripes, nearly equal in width to transverse bands; longitudinal dark stripe of mesopleuron slender, running about 1/2 of its length, very close to anterior margin but far from short acetabular mark; anterior transverse stripe of metanotum laterally confluent with posterior stripe of metanotum; fore femora with apical dark ring and four longitudinal marks, ventral mark connected with ring, remaining marks not confluent, inner mark relatively pale and bright, external mark broad and blackish brown; middle and hind femora yellowish, tibiae and tarsi black; abdomen mainly blackish dorsally, abdominal tergites II–IV blackish, abdominal tergites V–VII blackish anteriorly and yellowish posteriorly; abdominal segment VIII with a large rectangular blackish mark in dorsal view, posteriorly with moderately bifid-shaped. Genital segments yellowish. Structural characters: head length 0.51– 0.55, head width 1.61–1.69, minimum interocular width 0.67–0.70; antenna about 0.90 times as long as body, lengths of antennal segments I–IV: 2.71, 1.40, 1.18, 0.70; pronotum slightly narrower than head, pronotum length 0.66–0.70, pronotum width 1.87–1.90; fore femora moderately incrassate (Fig. 43), ratio length/width 4.5, inner side not modified, with a subapical indentation, and a small single apical tooth; inner surface of fore tibiae not modified (Fig. 43); lengths of leg segments (femur, tibia and tarsus): fore leg: 3.12, 2.52 and 1.01 (0.10+0.91), middle leg: 8.21, 6.11 and 3.01 (2.62+0.39), hind leg: 8.02, 6.23 and 1.02 (0.52+0.50); dorsum of abdomen clothed with short shiny golden hair, venter of abdomen densely clothed with pale yellow hairs. Male terminalia: abdominal segment VIII more or less rectangle (Fig. 48), relatively large, length 1.58, width 1.08, about 1.46 times as long as wide, posterior margin with dense brown erect hairs (Fig. 48); pygophore subovate (Fig. 53), proctiger laterally raised and with a pair of blackish dots (Fig. 58); paramere stout and triangularly curved upwards, lateral part with distinctly angular projection, apex narrowed and blunt (Figs. 66, 83). Endosoma (Figs. 71, 81, 82): dorsal sclerite long and recurved proximally, apical accessory sclerites small, accessory lateral sclerites thick and straight, ventral sclerites present and long.
Apterous female (Fig. 33). Body length 6.07–6.13, body width (across acetabula) 3.36–3.40. Colour similar to apterous male. Structural characters: head length 0.70–0.73, head width 1.57–1.61, minimum interocular width 0.62–0.65; antenna about 0.74 times as long as body, lengths of antennal segments I–IV: 2.01, 0.89, 0.91, 0.74; pronotum slightly narrower than head, pronotum length 0.47–0.50, pronotum width 1.67–1.71; fore femora slender without teeth, ratio length/width 6.9, inner surface of fore tibiae not modified; lengths of leg segments (femur, tibia and tarsus): fore leg: 2.75, 2.31 and 1.00 (0.12+0.88), middle leg: 6.81, 5.39 and 2.91 (2.31+0.60), hind leg: 6.78, 4.50 and 0.98 (0.53+0.45). Female terminalia: abdominal sternum VII relatively large, about as long as length of preceding abdominal sterna together, laterally constricted, apical half forming a broad lobe, caudal margin without median notch, not completely covering apex of abdomen in ventral view (Fig. 38).
Macropterous female and macropterous male. unknown.
Etymology. Named in honour of Prof. Leyi Zheng for his outstanding contribution to the studies on Heteroptera.
Distribution. China (Guizhou) (Fig. 84).
Comparative notes: M. zhengi sp. nov. fits the diagnostic characters of the M. lituratus group as defined by Chen & Nieser (1993). The general appearance of this new species is also similar to the M. sichuanensis Chen & Nieser, 1993. However, the distinctive paramere blade of M. zhengi sp. nov. is rather stout and triangularly curved upwards, and the lateral part bears a distinctly angular projection, with the blade apex narrowed (Figs. 66, 83), while in M. sichuanensis the paramere blade is relatively slender and straight, lacks an angular projection laterally, and has the blade apex slightly extended (Figs. 5, 10, 59–62). In addition, the larger size of abdominal segment VIII and pygophore (Figs. 48, 53), the thicker accessory lateral sclerites of the endosoma in dorsal view (Figs. 71, 81), and the caudal margin of female abdominal sternum VII lacking a median notch in M. zhengi sp. nov. (Fig. 38), are other important differences between these two closely related species.
description: Published as part of Chen, Zhen Ye Ping-Ping & Bu, Wen-Jun, 2016, Notes on the Metrocoris lituratus group (Heteroptera: Gerridae: Metrocoris) with descriptions of four new species in Sichuan Basin from China, pp. 359-374 in Zootaxa 4117 (3) on pages 372-373, DOI: 10.11646/zootaxa.4117.3.4, http://zenodo.org/record/269712