Acosmetura mabianensis Bian & Shi

Bian, Xun, Kou, Xiao-Yan & Shi, Fu-Ming, 2014, Notes on the genus Acosmetura Liu, 2000 (Orthoptera: Tettigoniidae: Meconematinae), Zootaxa 3811 (2), pp. 239-250 : 245-247

7. Acosmetura mabianensis Bian & Shi sp. nov.

( Figs 4 , 6 C, 7C, Map 1)

Description. Male. Body small. Fastigium verticis stout, apex obtuse, furrowed in midline. Eyes subglobular, protruding forwards. Apical segment of maxillary palpi as long as subapical one, apex slightly widened.

Pronotum short, anterior margin straight, posterior margin obtusely rounded, posterior transverse sulcus comparatively distinct, metazona slightly raised; lateral lobe longer than high, without humeral sinus.

Ventral surface of all femora without spines. Procoxae with a small spine; protibiae with 5 pairs of spines on ventral surface; tibial tympana open on inner and outer sides, oval. Mesotibiae with 5 and 6 spines on inner and outer sides of ventral surface. Genicular lobes of postfemora obtusely rounded, posttibiae with 25–27 inner spines and 26–28 outer spines of dorsal surface separately, apex with 1 pair of dorsal spurs and 2 pairs of ventral spurs.

Tegmina short, completely covered by pronotum, apices of tegmina obtusely rounded, which reaching middle area of second abdominal tergite; left stridulatory area large, fully developed. Stridulatory file elevated on thickened vein, weakly sinuous, 1.1 mm long, with about 69 teeth. Hind wings absent.

Posterior margin of tenth abdominal tergite with 1 nearly triangular concavity in middle. Basal area of cerci stout, slightly narrowing in lateral view; one third basal area concave ventrad, flat, apices of the inner margin nearly triangular; two thirds area of cerci slightly depressed, internal margin slightly carinate; apical area with a small, obtuse tooth. Genitalia sclerotized, apical half narrow, linguiform, apex slightly concave in middle. Basal area of subgenital plate comparatively broad, centre distinctly concave; lateral margins curved dorsad; apical area narrow, posterior margin slightly concave; with subconical styli on apices of lateral margins of subgenital plate.

Female. Similar to male with following exceptions: Pronotum comparatively short, posterior margin broadly rounded. Tenth abdominal tergite with a median concavity on posterior margin. Cerci conical, apices thin and acute. Ovipositor gently curved upwards, base stout, narrowing, dorsal and ventral margins smooth, apices acute. Subgenital plate semicircular in ventral view, basal margin nearly straight, baso-lateral margin triangular in lateral view, posterior margin nearly truncate, slightly concave in middle.

Coloration. Male body light yellowish green. Pronotum with a broad longitudinal brown stripe, which unconspicuous near posterior area of metazona, the outer margins with a pair of dark brown stripes. Dorsal surface of abdominal tergite with a longitudinal dark brown stripe.

Female lighter than male in pronotal disc and abdomen. Dorsum of head and pronotum light yellowish brown. Dorsal surface of abdomen with a broad longitudinal light brown stripe.

Measurements (mm). Body: ♂10.5–11, ♀15.0–15.5; pronotum: ♂4.6–5.0, ♀4.4–4.7; tegmen: ♂2.4–2.7, ♀2.0–2.5; postfemur: ♂10.0–10.5, ♀10.5–11.0; ovipositor: 6.5–7.0.

Material examined. Holotype: male, Yonghong, Mabian, Sichuan, China, 22 July, 2004, coll. by Fu-Ming Shi. Paratypes: 3 males and 11 females, other information as the holotype.

Discussion. The new species is allied Acometura nigrogeniculata ( Liu, 1998) , but it differs from the latter in: male tenth abdominal tergite with 1 nearly triangular concavity in the middle; one third basal area of male cerci concave ventrad, flake, apices of the internal margin nearly triangular; two thirds area of cerci depressed, internal margin slightly carinate; basal margin of female subgenital plate nearly straight, posterior margin nearly truncate, slightly concave in the middle.

Distribution. China (Sichuan).

Etymology. Name after the type locality of the new species, Mabian, in Sichuan Province.

Figures

FIGURE 4. Acosmetura mabianensis Bian & Shi sp. nov.: A – B, G – H. pronotum: A, G. dorsal view; B, H. lateral view; C – E, I. apex of abdomen: C, I. lateral view; D. dorsal view; E. dorso-lateral view; F, J. subgenital plate in ventral view; A – F. male; G – J. female.

FIGURE 6. Male left tegmen: A. Acosmetura nigrogeniculata (Liu & Wang, 1998); B. Acometura jinyunensis (Shi & Zheng, 1994) com. nov.; C. Acosmetura mabianensis Bian & Shi sp. nov.; D. Acosmetura forcipata Liu, Zhou & Bi, 2008.