Bioacoustics of Borneogryllacris xujuni

Description. Male. Large species. Face ovoid with sparse punctures ( Fig. 1A ). Fastigium verticis wider than scape. Apical segments of maxillary palpi slightly longer than subapical ones, apices faintly swollen ( Fig. 1A ). Apical segments of labial palpi obviously swollen. Ocelli distinct. Anterior margin of pronotum slightly projected, posterior margin arched; anterior angle of lateral lobes rounded, posterior angle slightly extending downwards ( Fig. 1B ). Humeral sinus indistinct. Fore coxae with 1 spine ( Fig. 1C ). Fore and middle femora unarmed on ventral surfaces; hind femora ventrally with 8–11 internal and 7–8 external spines. Fore and middle tibiae with 5 pairs of ventral spurs, including 1 pair of apical ones; hind tibiae with 5–6 pairs of spines on dorsal surface, apices with 1 pair of dorsal spurs and 2 pairs of ventral spurs. Second and third abdominal tergites with few largely reduced, indistinct stridulatory pegs or not ( Fig. 1E ). Eighth abdominal tergite prolonged. Ninth abdominal tergite globular, with a shallowly furrow in midline, basal area swollen on each side of furrow, at apex with an acute spine, its subapical area crossing each other and directing downward and forward ( Fig. 1F–G ). Subgenital plate wider than long, posterior margin with a triangular concavity ( Fig. 1H ); styli slightly longer than subgenital plate, inserted at apico-lateral angles ( Fig. 1H ). Female. Subgenital plate nearly trapezoidal; middle area of basal margin with 2 small black grooves ( Fig. 3G ); the lateral margins of basal areas convex, then narrowing, posterior margin bilobate ( Fig. 3E–F ). Ovipositor moderately upcurved, dorsal and ventral margins smooth, apices subacute ( Fig. 3H ). Wings. Tegmina justly reaching or slightly surpassing the apex of abdomen, but not reaching the apices of hind femora ( Figs. 1I–J , 3I ); hind wings slightly longer than tegmina. Tegminal veins ( Figs. 2 , 4 , 5 ): Radius with RS branching before apical third area of tegmen, both forked near tip; media anterior free from base, then it fuses with radius, after both veins separated again; cubitus anterior at base single branched, after divides into two branches before basal third, the anterior branch makes a curvature and receives a short connection branch from MA, shortly after it divides into MP and CuA1 (sometimes they do not reach the tip of tegmen ( Figs. 2A , 4A , 5C, E )), or not divided instead runs as fused MP+CuA1 till tip ( Figs. 2C , 5A ), the posterior branch (CuA2) undivided. Cubitus posterior undivided, free throughout; with 4 anal veins, the last two with common stem. Coloration. General color light brown ( Figs. 1I–J , 3I ). Head red, eyes black, ocelli pale yellow ( Fig. 1A , 3A ). Margins of pronotum black which extended at anterior and posterior margins, the posterior black band nearly V-shaped ( Fig. 1B , 3B ). Coxae with black spots, apical areas of femora and tibiae of all legs rufous ( Figs. 1I–J , 3I ). Tegmina yellowish brown, towards anterior and posterior margins lighter; basal area with large black spots surrounding an orange spot in middle; veins brown ( Figs. 2 , 4 , 5 ). Each abdominal tergite with black band on posterior margin; each abdominal sternite with 1 pair of black spots. Apical half of female subgenital plate and ovipositor black ( Fig. 3H ).