Apotrechus trilobus Bian & Shi

Bian, Xun, Wang, Shuai-Yu & Shi, Fu-Ming, 2014, One new species of the Genus Apotrechus (Orthoptera: Gryllacrididae), with provided morphological photographs for five Chinese species, Zootaxa 3884 (4), pp. 379-386 : 384-386

7. Apotrechus trilobus Bian & Shi sp. nov.

( Fig. 6 )

Male. Body medium. Wings absent. Fastigium verticis broad, about half as broad as scape. Eyes ovoid; ocelli inconspicuous. Scape as long as pedicel and first article of flagellum combined. Anterior margin of pronotum slightly excavate, posterior margin nearly truncate, ventral margin of lateral lobes undulated, humeral sinus indistinct. Fore coxae with 1 small spine; fore and middle femora unarmed on ventral surface; fore tibiae with 5 pairs of ventral spurs and middle tibiae with 4 pairs of ventral spurs. Hind femora with 5 inner spines and 4 outer spines on ventral surface; hind tibiae with 4–5 pairs of reduced spines on dorsal surface, apex with 1 pair of dorsal spurs and 2 pairs of ventral spurs. Second and third abdominal tergites with 2 rows of transverse stridulatory teeth on lateral margins separately. Ninth abdominal tergite curved downwards, split into 2 lateral lobes by deeply Vshaped incision, each bearing one hook at apex, which pointed inside and forward. Cerci conical, nearly straight, apices subacute. Subgenital plate without styli, broader than long, posterior margin with a median concavity, the lateral lobe obtusely rounded, apex of lateral lobe with 1 small process, digitate in apico-lateral view ( Fig. 6 F).

Body yellowish brown. Eyes brownish; occiput with 1 semicircular transverse black brown stripe, which split in middle, outer area with 1 pair of short black stripes ( Fig. 6 B); fastigium verticis with 3 small black spots; frons with 1 pair of vertical black stripes beneath antennal foveolae and 1 vertical black stripe in middle ( Fig. 6 A); apical part of mandibles black; inner margin of antennal socket, basal area of scape and pedicel, and basal articles of flagellum black brown, the other part of flagellum lighter. Pronotum with black margins, in the disc with 1 longitudinal black stripe. Mesonotum, metanotum and first abdominal tergite with black margins and a median black stripes separately. Apical area of fore and middle femora black brown, basal area and apical area of tibiae black and all spines on hind legs black brown.

Female. Appearance is similar to male. Subgenital plate short, basally broad, apical half slightly narrowing, basal margin excavate, lateral margin triangular expanded, posterior margin slightly projecting in middle ( Fig. 6 L). Ovipositor short, dorsal and ventral margins smooth, base stout, narrowing, apical half curved upwards, apex obtuse.

Measurements (mm). Body: ♂ 17.0–17.5, ♀ 21.0–22.5; pronotum: ♂ 3.5–4.0, ♀ 4.0–4.2; hind femora: ♂ 8.0–9.5, ♀ 9.0; ovipositor: ♀ 5.0–6.0.

Material examined. Holotype, male, Daxueshan, Weixin, Yunnan, 19 August, 2013, collected by Xun Bian & Guang-Lin Xie. Paratypes: 2 females, other data as the holotype; 1 male, Xiaocaoba, Yiliang, Yunnan, 24 August, 2013, collected by Xun Bian & Guang-Lin Xie.

Distribution. China (Yunnan).

Remarks. The new species is very similar to Apotrechus fallax Liu & Bi, 2008 , but differs in: frons with 1 vertical black stripe in middle; lateral lobes of male subgenital plate with 1 pair of apically processes, which digitate in apico-lateral view; lateral margin of female subgenital plate triangular expanded in middle, posterior margin slightly projecting in middle.

Etymology. The name of the new species is derived from the triangular expansion of female subgenital plate in middle area.

Figures

FIGURE 6. Apotrechus trilobus Bian & Shi sp. nov.: A, H. head in frontal view; B – C, I – J. head and pronotum: B, I. dorsal view, C, J. lateral view; D – F, K. apex of abdomen: D. dorsal view, E, K. lateral view, F. apico-lateral view; G, L. subgenital plate in ventral view; A – G. male, holotype; H – L. female, paratype.