Bioacoustics of Nahlaksia bidadari

Description. — Fastigium verticis conical but step-like inclined in circa half of length, with lateral ocelli projecting laterad; apex sub-obtuse; dorsal surface furrowed and without a tubercle near base; ventral surface with medial carinula. Fastigium frontis with one or two tubercles in midline. Frons rugose and setose; only immediately below antennal scrobae furrowed and smooth ( Fig. 1B ). Fastigium verticis and vertex in anterior area rugose; vertex otherwise subsmooth but with some impressed dots. Pronotum rugose, rather short, regularly curved from one side to the other; transverse sulcus weak, interrupted in middle, a second transverse sulcus on paranota and angles; anterior margin broadly rounded, slightly concave at both sides; posterior margin concave; paranota longer than high, ventral margin subsinuate, anterior angle rounded, posterior angle circa rectangular but angle itself rounded; humeral sinus absent. Tegmen: Male micropterous ( Fig. 1C ), female squamipterous ( Fig. 1E ). Prosternum unarmed, with two minute tubercles at posterior margin; meso- and metasternal lobes rounded. Femora, especially mesofemur, compressed and widened in basal area; mesotibia compressed and widened. Legs setose. Profemur with spines on both ventral margins, meso- and postfemur on ventro-external margin; sometimes with one spine on ventro-internal margin of mesofemur. Knee lobes of all femora rounded on external, spinose on internal side; spine on mesofemur shorter than on pro- and postfemur or lobe triangular without spine. Protibia distinctly angular. Femora with the following number of spines on ventral margins: profemur 3–4 external, 3–5 internal; mesofemur 4–6 external, 0 internal; postfemur 5–8 external. Male: Stridulatory file on underside of left tegmen about 1.0 mm long with teeth gradually getting denser from base to apex; in basal half with about 44, in centre with about 54 teeth per 0.5 mm ( Fig. 2A ). Tenth abdominal tergite elongate with a pair of large roughly triangular apical lobes with convex surface and downcurved medial margin ( Fig. 2C ). Epiproct hidden under prolongation of tenth abdominal tergite, tongue-shaped with faint medial furrow ( Fig. 2D ). Cerci conical in external view but little compressed laterally and internal surface flattened, apical area bent ventrad and compressed, apex obtuse, with a spinule a little externally of tip ( Fig. 2B ); cercus at base with a stout conical dorsointernal projection with subacute apex ( Fig. 2D ). Subgenital plate with apex extended into two short, narrow lobes, wide roundly excised in between; styli long, inserting at apex of projections ( Fig. 2E ). Titillators simple, weakly sclerotised, hyaline along lateral margins; apical area compressed with granular surface; sclerotised central ligament widening towards rounded apex ( Fig. 2F ). Female: Tenth abdominal tergite with a very faint carinula in midline, apical margin faintly bilobate in middle, otherwise subtruncate. Epiproct rounded-triangular with medial furrow that is little widening apically. Cerci conical, apex pointing. Subgenital plate curved from one side to other, lateral margins convex, converging posteriorly, apex roundedly excised in middle ( Fig. 1F ). Ovipositor curved, elongate; margins smooth, dorsal valves furrowed ( Fig. 1G ). Colouration: Ochre or brown with irregular light and dark pattern; with or without few green spots. Frons including fastigium frontis and antennal scrobae black ( Fig. 1B ); sometimes less dark in middle; mouthparts reddish or brown; labrum partly orange; palpi brown, apices of most segments pale; antennae brown with spaced white annulation, first two segments with black marks. Hind area of genae brown; compound eyes light; ventral margin and a spot near scapus black. Vertex and pronotum brown with various shades of a dark and light pattern, sometimes infumate with green pattern. Tergites ochre, medium or dark brown with small light dots that partly merge to form larger spots; with fairly distinct dark medial band; sternites yellow mottled with brown or dark or reddish brown; thoracic sternites can be nearly blackish brown. Legs with various shades of brown and marbled with whitish dots of variable size; ventro-internal lobes of meso- and metacoxa nearly white, sometimes indistinct; ventral areas of all femora reddish brown, darker towards tronchanter; tronchanter dark reddish brown; very base of tibiae black or dark brown, spines whitish with dark tips; hind femur reddish brown, sometimes with light dots on outer face; dorsal areas of profemur, protibia, mesotibia, posttibia can additionally become infumate with a green pattern, sometimes indistinct. Ovipositor dark reddish brown apically, lighter reddish brown basally. Measurements ( 5 males , 6 females ): Body: male 18.2–22.1, female 19.0–22.1; pronotum: male 4.5–5.7, female 5.4–5.7; tegmen: male 1.9–2.9, female 0.5–1.5; hind femur: male 8.4–9.6, female 10.1–10.8; ovipositor: female 11.6–12.8; ovipositor height: female 1.5–1.7 mm .