Bioacoustics of Apterolarnaca biloba

( Figs. 1–5 , 12–13, 17–18 ) Male. Body medium. Wings absent. Fastigium verticis nearly rounded, about 2 times as broad as scape. Eyes ovoid; ocelli inconspicuous. Pronotum nearly hexagon, anterior margin nearly straight, posterior margin somewhat retuse; lateral lobes of pronotum longer than high, humeral sinus indistinct. Mesonotum and metanotum slightly longer than first abdominal tergite. Fore coxae with 1 spine; femora unarmed; tibiae with 5 pairs of spurs (including 1 pair of apical spurs) on ventral margins. Middle femora unarmed; tibiae with 4 pairs of spurs (including 1 pair of apical spurs) on ventral margins and 1 inner upper apical spur. Hind femora with 6–9 inner spines and 2–5 outer spines on ventral margins; tibiae with 2–5 inner spines and 4–6 outer spines on dorsal margins, which are very small, 1 pair of apical spurs on dorsal margins and 2 pairs of apical spurs on ventral margins. Second abdominal tergite with 2 rows of transverse stridulatory teeth on lateral margins and the anterior row very short, only 2–3 stridulatory teeth; third abdominal tergite also with 2 rows of transverse stridulatory teeth on lateral margins, both rows of stridulatory teeth long; eighth abdominal tergite slightly longer than seventh abdominal tergite; ninth abdominal tergite curved downwards, cuculliform, split into 2 lateral lobes, which bearing hook on apices. Subgenital plate without styli, significantly broader than long, middle of apical part strongly concaved. Cerci short, conical. Body yellowish brown. Eyes black; occiput with 1 semicircular black transverse stripe, but split in middle; fastigium verticis with 3 small black spots, frons with 1 pair of black vertical stripes beneath antennal foveolae; apical part of mandibles black; inner margins of antennal foveolae and inner margin of scapes with black spots, antennal blackish except scape and pedicel. Pronotum with black margins, in the middle of pronotum with 1 black vertical stripe which with pale midline. Mesonotum and metanotum with black margins, both with 1 pair of black spots at middle parts. Basal area and apical area of tibiae, all spines on hind legs, and fine spots at bases of spines on hind tibiae, all black. Apices of hooks on ninth abdominal tergite blackish brown. Female. Similar to male in appearance and coloration, body slightly larger. Subgenital plate slightly broader than long, posterior margin rounded. Ovipositor short, about 1/2 times as long as hind femur, dorsal and ventral margins smooth, apex rounded, strongly curved dorsal; with 1 pair of well-developed digitate lateral lobes at base of lower sheaths. Measurements(mm) . Body: 315.0–17.5, Ƥ20.0–22.0; pronotum: 33.5, Ƥ4.0–4.2; hind femora: 38.0–9.5, Ƥ9.0; ovipositor: Ƥ4.7–5.0.