Bioacoustics of Metriogryllacris (Metriogryllacris) prunulis

Figures 2–3 Description. Male. Body medium with wings. Head. Face smooth without distinct transverse fold ( Fig. 2A ). Fastigium verticis wide, approximately two times as wide as the width of the scapes. Eyes oval, ocelli indistinct. Thorax. Anterior margin of pronotum slightly projecting, posterior margin widely arched ( Fig. 2B ); lateral lobes nearly trapezoidal, longer than high, anterior angle rounded, posterior margin oblique, humeral sinus indistinct ( Fig. 2C ). Fore coxae with 1 small spine. Fore and middle femora unarmed on ventral surfaces; hind femora with 13–14 internal spines and 10–11 external spines on ventral surface. Fore and middle tibiae ventrally with 4 pairs of spurs and 1 pair of apical spurs, middle tibiae with 1 apical spur on internal margin of dorsal surface; hind tibiae dorsally with 6 pairs of spines, subapices ventrally with 1 pair of spurs, apices with 1 pair of dorsal spurs and 2 pairs of ventral spurs. Tegmina reaching the posterior margin of seventh abdominal tergite and extending to the apices of hind femora; hind wings slightly longer than tegmina. Abdomen. Lateral margins of second abdominal tergites with two rows of twisted stridulatory pegs. Lateral margins of third abdominal tergite with two rows of subparallel stridulatory pegs ( Fig. 2D ). Eighth abdominal tergite long, significantly prolonged backward ( Fig. 2E ); ninth abdominal tergite significantly curved ventrally, middle area of posterior margin with 1 pair of small processes ( Fig. 2G ), widely separated from each other, hook-shaped in lateral view ( Fig. 2E ), apical margin arched. Cerci conical and short. Subgenital plate slightly longer than wide, basal margin straight, lateral margins convex, posterior margin rounded projecting; styli nearly cylindrical, apices obtuse, inserted on both sides of subapical areas of subgenital plate ( Fig. 2I ). Female. Abdomen. Basal margin of seventh abdominal sternite faintly concave; lateral margins with basal half convex, apical half converging; posterior margin narrowly rounded; ventral surface of apical half concave, posterior margin of the concave separated by a furrow along the midline and the lateral margins sclerotized, at tips with 1 copulatory depression on each side ( Fig. 3C ). Subgenital plate wider than long, lateral margins converging, posterior margin faintly arched ( Fig. 3C ). Ovipositor short, apart from subbasal curvature straight, apices obtuse; base of ventral valvulae with 2 pairs of long processes ( Fig. 3C ). Coloration. Body yellowish brown, eyes brown. Margins of pronotum brown. Apices of spines of hind leg black brown. Apices of male eighth and ninth abdominal tergites reddish brown. Measurements (mm). BL: ♂ 17.0–19.4, ♀ 14.8–16.5; PL: ♂ 3.7–4.2, ♀ 4.4–5.0; TL: ♂ 11.8–12.6, ♀ 11.4– 12.5; HFL: ♂ 9.4–9.8, ♀ 10.1–10.4; OvL: 7.6–9.1.