Bioacoustics of Trichophallus borneensis

Diagnosis. Males of T. borneensis can be recognised by the shape of the elongate and rather narrow cerci that have the end bent mediad and with acute tip and from about mid-length a narrow, conical internal projection also with acute tip. Females are unique for the shape of the subgenital plate that is completely divided in mid-length into two halves which have the dorsal extension curved into a semi-circle and the main part prolonged into narrow apical lobes. Male. Stridulatory file with about 102–127 teeth. Tenth abdominal tergite with central area slightly prolonged behind, with two faint obtuse projections at apex and area in between depressed and truncate or little concave. Epiproct in dorsal view with almost parallel lateral margins, deeply furrowed in midline; in apical view V-shaped. Paraprocts with a curved projection from internal margin. Cerci almost straight, in dorsal view with a broader basal half and a narrower apical half; with a large, acute, internal tooth in middle of length and another, acute, internal tooth at apex. Subgenital plate almost rectangularly excised at apex; styli of about same length as excised area. Titillators separate, rather simple with transversely truncate apex with acute tip; at truncation connected to a weakly sclerotised sub-hyaline plate narrowing towards apex, and at apex terminates into a long acute thorn; titillators and projecting plate supporting part of inner surface of long, compressed, elongate, membranous bursae with globular bellied base; below margin of globular base with a row of long bristles; external surface of membranous sacks completely covered with dense dark hairs; with two pairs of granular lateral sclerites: small roughly oval sclerites near apex and elongate about canoe-shaped sclerites near middle of titillators. Female. Tenth abdominal tergite deeply excised in midline. Epiproct triangular with a deep medial furrow, in apical view V-shaped. Subgenital plate divided in midline by a narrow membranous suture; basal area narrow; apical lobes twisted with ventral internal margin bulgy, apical area triangularly projecting sidewards with apical angle rounded and lateral angle acute; basal-lateral areas greatly extended dorsad, auricular with grooved surface. Eight abdominal tergite with lateral-posterior angle cut out for half of tergite length, remaining area roundly projecting, forming a cavity between lateral area of tergite and the setose subgenital plate. Ovipositor rather short and stout; dorsal margin of ventral valves without projecting lobe at base. Measurements ( 1 male , 3 females ).—body w/o wings: male 20, female 16–22; pronotum: male 4.5, female 4.2–4.9; tegmen: male 21, female 21–23; hind femur: male 13, female 13.0–13.5; ovipositor: female 9–10 mm .