Bioacoustics of Ocellarnaca angulata

Description. Rather short and stout species ( Fig. 101F ). Head: Face ovoid; forehead nearly smooth with some scattered impressed dots and very fine transverse riffles; fastigium verticis moderately wider than scapus, separated by a transverse suture from fastigium frontis; ocelli very distinct, light yellow; median ocellus very large ( Fig. 22M ). Abdominal tergites two and three each with two rows of stridulatory pegs. Wings shortened, in male about reaching tip of abdomen but not hind knees, in female leaving last abdominal tergites uncovered ( Figs. 21 E–F). Tegmen: Radius with two branches: both unforked or RS forked once; media anterior has a common stem with radius, arising as first posterior branch of radius at about end of basal third; media posterior absent; cubitus anterior undivided; cubitus posterior undivided, free throughout; with 5 anal veins. Legs: Fore coxa with a large spine at fore margin; fore and mid femora unarmed; fore and mid tibiae with 4 pairs of large ventral spines and one pair of smaller ventral spurs; hind femur with 6–8 external and 14–15 internal spines on ventral margins; hind tibia with spaced spines on both dorsal margins, ventral margins with one preapical spine; with 3 apical spurs on both sides. Coloration. General color brown without distinct pattern except for wings; vertex with dark spots at internal margins of compound eyes, variation: male with black spot at hind margin of pronotum, male with black hind margin. Face uniformly brown except for light ocelli; mandibles black. Tegmen dark brown with light colored veins and veinlets; hind wing yellowish or light brown, veins little darker, the cells between veins and cross-veins with a dark brown spot in middle, borderlines light. Male. Ninth abdominal tergite globular, apical surface furrowed and then angularly divided, medio-ventral angles extended into a narrow, little curved and dorsally flattened process with acute tip; above base of process with another process that is black, dorso-ventrally compressed but little vaulted and with rounded tip ( Figs. 23 D– E). Subgenital plate wider than long with medial furrow, posterior-central area little depressed, lateral margins convex, apical margin truncate but at end of medial furrow little projecting; styli shorter than plate, inserted inside of latero-apical angles ( Fig. 23F ). Female. Seventh abdominal sternite prolonged, simple; with 2 small membranous extensions at hind margin. Subgenital plate wide at base with concave, approaching lateral margins, apical margin roundly excised, on both sides with subacute angles; basal and central areas and lateral margin in mid-length membranous, only lateral margin at base and apical area sclerotised; lateral margins in apical area strongly swollen with widening furrow in between ( Fig. 24E ). Ovipositor elongate, strongly curved in basal area, slightly curved thereafter, lateral surface furrowed, margins gradually approaching towards apex; tip subacute ( Fig. 22N ). Measurements ( 12 males , 5 females ).—body w/wings: male 22–32, female 28–34; body w/o wings: male 22– 32, female 24–34; pronotum: male 6.0–7.5, female 7.0–8.5; tegmen: male 8.0–18.5, female 10–18; tegmen width (in large specimens): male 7.5, female 7; hind femur: male 14.0–18.5, female 17.0–18.5; antenna: male 85–170, female 100–150; ovipositor: female 19–21 mm . There is a remarkable polymorphism in size and wing length between populations.