Bioacoustics of Tenuigryllacris fruhstorferi

Description. Small, apterous species ( Figs. 74 A–C). Head: Face ovoid, forehead with scattered impressed dots and few fine transverse riffles; fastigium verticis little wider than scapus, separated by a fine suture from fastigium frontis; ocelli little distinct; subocular furrow shallow ( Fig. 74D ). Abdominal tergites two and three each with two rows of stridulatory pegs (5 indistinct, 12; 13, 15; male type ). Wings: apterous, thoracic tergites 2–3 with faint, narrow oval projection at lateral margins. Legs: Fore coxa with a spine at fore margin; fore and mid femora unarmed; fore and mid tibiae with four pairs of large ventral spines and one pair of smaller ventral spurs; hind femur with 2–3 external and 2–4 internal spines on ventral margins; hind tibia with spaced spines on both dorsal margins, ventral margins without pre-apical spine; with 3 apical spurs on both sides. Coloration. General color yellow brown with black lateral bands from behind compound eyes to eighth abdominal tergite, in male eighth tergite black with brown spot at anterior margin, ninth tergite completely black; legs of general color, tibiae with a sub-genicular dark spot. Face yellowish brown with some darker spots, differing between specimens. Male. Eighth abdominal tergite prolonged. Ninth abdominal tergite prolonged, not globular, lateral margins in dorsal view narrowing posteriorly, lateral surfaces curved down, forming a large, tube-like posterior opening. Tenth abdominal tergite forming a pair of strongly swollen, ovoid sclerites, terminating into a stout, curved, acute spine on medial side; those ovoid sclerites are embedded in the intersegmental membrane and leaning on the internal surface of the tube-like opening of the ninth abdominal tergite ( Figs. 75A, C ). Epiproct in middle with a pair of large, laterally compressed projections down-curved towards and acute at tip. Subgenital plate longer than wide with diverging lateral margins, terminating into two large semi-ovoid diverging lobes, angularly excised in between; small styli inserted at tip of apical lobes ( Fig. 75B ). Female. Seventh abdominal sternite little longer than preceding sternites, otherwise normal. Subgenital plate with a pair of large, shallow baso-lateral grooves, subparallel lateral margins and apex bilobate ( Fig. 75D ). Ovipositor short, upcurved, and rather strong and regularly narrowing from base to tip; tip subobtuse ( Fig. 75E ). Measurements ( 2 males , 2 females ).—body w/o wings: male 18–20, female 20–24; pronotum: male 3.8–4.2, female 4; hind femur: male 9.5–10.0, female 9; antenna: male 70, female 60–80; ovipositor: female 7.5 mm .