Trichophallus aru Ingrisch 2024, sp. nov.

Figs. 23–24

Holotype (male): Indonesia: Aroe Eilanden, Manoembai en omgeving, 11–44, (6°2‘S, 134°18‘E), 1–31 October 1929, Snellius Expedition; depository: Naturalis Leiden.

Other specimens studied: Indonesia: Maluku, Aru Islands, Manoembai en omgeving, 11–44, (6°2‘S, 134°18‘E), 1–31.x.1929, coll. Mus. Leiden, Snellius Exp. — 5 females, 4 males (Naturalis Leiden).

Diagnosis. The new species can be recognised by the shape of the rather narrow male cerci with converging margins and a short triangular, sub-apical internal projection. The shape of the male titillators is also characteristic. Females have the basal-lateral extensions of the subgenital plate relatively short, the central area short, and the apical projections moderately long and narrow in ventral view but rather high in lateral view.

Description. Medium sized species. Tegmina surpassing middle of hind tibia. Femora with the following number of spines on ventral margins: fore femur 6–9 external, 6–9 internal; mid femur 6–10 external, 3–5 internal near base; hind femur 11–15 external, 11–17 internal.

Male. Stridulatory file with about 107–115 teeth. Tenth abdominal tergite terminating into two compressed lobes slightly approaching each other posteriorly, roundly excised in between. Epiproct triangularly rounded, surface without pit. Cerci narrow, with little approaching margins, and toward end slightly down-curved; in sub-apical area with a short but wide, obtuse-angular, subapical-internal projection with rounded tip. Subgenital plate with apex triangularly excised; styli a little longer than excised area. Titillators consisting of three pairs of sclerites: the basal pair simple, slightly curved and with approaching margins from rounded base to subacute tip, the central pair long, compressed, with both ends rounded, in basal area wide and in apical area sickle-shaped; the third pair is formed by the elongate and narrow lateral sclerites. The area that holds the first and second pair of sclerites together is formed by membranous structures that carry bulks of long hairs and bristles.

Female. Tenth abdominal tergite furrowed, apex with two short angular projections at both sides of midline. Subgenital plate with a weak medial carina; lateral angles of basal area swollen; apical lobes inserted at or a little dorsad of lateral angle, rather short, compressed, conical with rounded apex; basal-lateral areas only little projecting dorsad (little shrunk due to former preservation in alcohol and not well conserved). Eight abdominal tergite only little excised at lateral-posterior angles. Lateral areas of eight abdominal tergite, apical area of seventh abdominal sternite and ventral margin of ovipositor base setose; otherwise ventral ovipositor valves unmodified.

Coloration. (formerly preserved in alcohol). Yellowish brown with only pattern 1.

Measurements.—body: male 19–23, female 21–24; pronotum: male 5.8–6.2, female 5.8–6.2; tegmen: male 33.0–35.5, female 35–37; hind femur: male 17–18, female 17.5–18.5; antenna: male 80, female 75–80; ovipositor: 13 mm.

Etymology. The name of the new species refers to the type locality, the Aru Islands.