Pseudoxistrella Liang, 1991

Yu, Sergey & Omelko, Mikhail M., 2012, Review of the genus Pseudoxistrella Liang, 1991 (Orthoptera: Tetrigidae, Metrodorinae), Zootaxa 3573, pp. 59-65 : 59-60

Genus Pseudoxistrella Liang, 1991

Pseudoxistrella Liang, 1991: 95 ; Blackith, 1992: 153; Liang & Zheng, 1998: 127, 242, 247; Otte, 1997: 140; Zheng, 2005: 110, 455.

Type species: Pseudoxistrella eurymera Liang, 1991 , by original designation.

Description. Body slender, slightly granulated ( Fig. 1 ). Antennae filiform, 14-segmented ( Fig. 2 ), 2.5-2.6 times longer than fore femora; antennal bases situated below lower margin of eyes ( Fig. 4 ). Eyes protruding above pronotum in lateral view ( Fig. 9 ), and distinctly separated from anterior margin of pronotum in dorsal view ( Fig. 3 ). Fastigium of vertex near the middle of eyes slightly narrower than width of one eye in dorsal view, anterior margin of fastigium broadly rounded and reaching anterior edge of eyes; median carina of fastigium reaching the mid of eyes ( Fig. 3 ); in frontal view fastigium of vertex forming V-shape shallow concavity ( Fig. 4 ). Frontal ridge in lateral view with excision below antennal sockets ( Fig. 2 ); lateral carinae of frontal ridge in frontal view closely related one to another especially between antennal sockets ( Fig. 4 ).

Pronotum in dorsal view with straight anterior margin; posterior process of pronotum very long, surpassing far beyond the apex of abdomen. Median carina of pronotum low, almost straight ( Fig. 9 ); lateral carinae in prozona reduced or distinct, parallel-side ( Fig. 1 ). Hind margin of lateral lobes of pronotum bisinuate, tegminal (upper) sinus almost as deep lower sinus ( Fig. 9 ); posterior angle of lateral lobes pronotum rounder and turned downward ( Fig. 1 ). Tegmina ovate; hind wings long, extending or slightly exceeding the apex of posterior process of pronotum. Legs elongated; fore and mid femora with almost straight and gentle dentate upper and lower carinae ( Fig. 5 ); hind femora with gentle dentate upper carina and almost completely smooth lower carina ( Fig. 8 ). First segment of fore legs slightly shorter than second segment (without claws) and widened, 2.2–3 times as wide as second segment ( Fig. 6 ); first tarsal segment of mid legs also widened, but distinctly shorter than second one; pulvilli (ventral pads of tarsi) of the basitarsus of fore and mid legs are fused in the large sucker ( Fig. 7 ). First tarsal segment of hind legs 2.1 times longer than 3rd segment (without claws); dorsal side of 1st segment with three triangular pads ( Fig. 8 ). Male subgenital plate in lateral view short, conical ( Fig. 10 ). Female subgenital plate with pointed posterior margin ( Fig. 12 ). Valves of ovipositor narrow, dentate ( Fig. 11 ).

Diagnosis. Pseudoxistrella is closely related to the genus Xistra Bolívar, 1887 (sensu Zheng & Zeng, 2011), but easy distinguished from latter, as well as from all other genera of subfamily Metrodorinae , by almost completely fused lateral carinae of frontal ridge.

Composition. There are two species from China and Vietnam, one of which is described below.

Figures

FIGURES 1 – 4. Pseudoxistrella belokobylskii sp. nov. 1, male head and pronotum, dorsal view; 2, male antenna, dorsal view; 3, male head and anterior part of pronotum, dorsal view; 4, male head, frontal view. Scale bars 1 mm.

FIGURES 5 – 12. Pseudoxistrella belokobylskii sp. nov. 5, male fore leg, lateral view; 6, male fore tarsus, dorsal view; 7, the same, ventral view; 8, male hind leg, lateral view; 9, male head and anterior part of pronotum, lateral view; 10, male apex of abdomen, lateral view; 11, female apex of abdomen, lateral view; 12, the same, ventral view. Scale bars 1 mm.