Bioacoustics of Obolopteryx eurycerca

Description of males alive. Small size (14.1± 1.9 mm )., compared to congeneric species. Body slender. General color light green. Face yellowish-green, eyes elliptical very prominent, vertex and occiput brown. Fastigium of vertex compressed, almost in contact with the fastigium frontalis, in dorsal view; fastigium frontalis small sub–conical, compressed, distally rounded, in frontal view; antennae reddish-brown-proximally, remaining portion blackish with whitish-creme joints, white post ocular band delicate, extending onto sides of pronotum and abdomen ( Figs. 1 –3, 16b). Pronotum ( Figs. 1–2 , 16 b) dark brown-reddish, constricted mesially; typical sulcus on pronotal disc deep U-shape over the metazone; anterior and posterior margins moderately emarginated; lateral lobes of pronotum about twice wider than deep. Tegmina ( Figs. 1–2 ) short, slightly surpassing the posterior margin of the first abdominal tergite, mostly brown, except for a broad ventral margin band and veins that are white. Length of stridulatory file 6.6 mm ( Fig. 4 ) with ca. 92 teeth, average 14 (10–22) teeth/mm. Fore and mid femora with proximal third green color, remaining portion reddish-orange, hind femora proximal half green, then reddish– orange, distally black; tibiae reddish-orange proximally, remaining external portion black, internal face-yellowish– orange. Abdomen ( Fig. 16 b) dorsally dark-green-brown, with minute dark brown spots, two dorso lateral bands on each side, the lower one white and delicate, above this a conspicuous dark brown-black band; tenth tergite distodorsal projection ( Fig. 5 ) shallow U-shape forming two broad distal angles. Cerci ( Figs. 5 , 7–8 ) made up of two processes, a robust and moderately elongated dorsal thumb ventrally concave with rounded apex; a ventral shaft very produced and curved inwards, moderately broad proximal, tapering gradually towards the acute apex. Subgenital plate ( Fig. 8 ) elongated, lateral margins emarginated, distally shallow V-shape with broad emarginated margins, lateral angles diverging. Internal genitalia as shown in Figs. 9–10. Description of females (alive). Similar to the males, but more robust ( Figs. 11 , 16a ). General body color lightgreen, fastigium brown, vertex and occiput green with a broad dark brown band on each side; antennae’s socket green, scape, pedicel and basal segments reddish-orange, remaining portion brown-blackish with whitish-creme joints. Pronotum brown-green with reddish-brown marks, a broad reddish-brown band along midline, constricted mesially, posterior margin reddish-brown, with white marks, white post ocular band delicate and extending onto sides of pronotum and abdomen. Tegmina very short, reaching the caudal margin of metanotum, widely separated from each other, about twice broader than long, ventral margin white, the remaining portion reddish-brown with white veins. Abdomen with delicate dark brown lateral bands, one each side ( Fig. 16a ), and tiny brown spots dorsally and ventrally. Ovipositor (Fig. 13, 16a) moderately produced and visibly curved, length about head and pronotum combined, dorsal margin reddish-brown with 10–11 pairs of spines distally, a second row of six smaller spines distally along the ovipositor’s mid line; ventral margin with 9 pairs of spines distally and a second row of 8– 9 external smaller spines. Subgenital plate ( Figs. 14 –15) represented by two robust sub-triangular pilose structures, ovipositor’s lobe (Figs. 13–14) sub-trapezoidal; basal sclerites ( Figs. 14 –15) sub-circular, in ventral view, the outer portion broader projected between the ovipositor’s lobe and the subgenital plate, and the inner portion projected ventrally. Measurements (mm). Males: Body length from vertex to end of abdomen: 14.1±1.9 (12.8–15.5). Pronotum length: 3.1±0.5 (2.8–3.5). Tegmina length: 3.1. Fore femur length: 11.3±1.9 (10.0–12.7). Mid femur length: 12.6±1.5. Hind femur length 25.6. Females: Body length from vertex to end of abdomen: 14.7 (±1.4). Pronotum length: 3.7 ± 0.1 (3.6–3.8). Tegmina length: 1.0±0.2 (0.8–1.1). Fore femur length: 8.7±0.3 (8.5–8.9). Mid femur length: 9.6±0.8 (8.7–10.2). Hind femur length: 20.0±1.9 (17.9–21.2). Ovipositor: 7.4±0.6 (6.7–7.8). Inter–tegmina space: 1.0±0.1 (1.0–1.1).

Diagnosis . At first sight s imilar to O. castanea (Rehn & Hebard, 1914) , easily distinguished from the latter species by its smaller size (14.1±1.9 vs. 17.9± 2.7 mm ). Fastigium of vertex more delicate, smaller and less prominent (Fig. 3a vs. 19a); fastigium frontalis, in ventral view, not as broad as in O. castanea , distally more produced and compressed (Fig. 3b vs. 19b). Pronotum shorter and different tegmina ( Fig. 2 vs. 18). The length of the stridulatory file is 6.6 mm , with ca . 92 teeth, average 14 (10–22) teeth/mm, in O. castanea the length of the stridulatory file is 8.3 mm approximately, with ca. 147 teeth and an average of 18 (8–35) teeth/mm ( Fig. 4 vs. 20). The tenth tergite’s membranous distal projection ( Fig. 5 vs. 22) and the epiproct (Fig. 6 vs. 22) are clearly different. The cerci ( Figs. 5 , 7–8 vs. 21, 23–24), subgenital plate ( Fig. 8 vs. 24), and internal genitalia (Figs. 9–10 vs. 25–26) are dissimilar of analogous structures in O. castanea . In females the whitish-creme postocular band that extends onto pronotum sides is very delicate, and the pronotum typical carinae is wide U-shape ( Fig. 12 vs . 27), these characters are not so in O. castanea . Tegmina are mostly dark brown, except for the ventral margin band and veins that are white, in O. castanea the tegmina are almost entirely white ( Figs. 12 , 16a vs. 27, 32a, 32b). The ovipositor, subgenital plate and basal sclerites differ from homologous structures in O. castanea (Figs. 13–15 vs. 28–30).