Tiruvaca subcostalis Walker

Thermesia subcostalis Walker, 1865, List Specimens lepid. Insects Colln Br. Mus., 33: 1059.

Thermesia falcata Pagenstecher, 1886, Jb. nassau. Ver. Naturk., 39: 141.

Tiruvaca subcostalis Walker; Holloway, 1976: 38.

Diagnosis

This and Tiruvaca hollowayi Kobes have facies typical of the genus, and show sexual dimorphism. In males of subcostalis the fasciation is weaker than in the female, and the forewing has distorted venation and paler patches over the central part of the wing, whereas in hollowayi Kobes the fasciae are pronounced in both sexes, but the male has the distal margin excavate subtornally. The species can most reliably be distinguished by the medial and postmedial fasciae of the hindwing: these converge towards the costa in hollowayi but run parallel towards it in subcostalis.

Geographical range

Thailand, Peninsular Malaysia and Borneo to Solomons.

Habitat preference

The species is rare in the lowlands where it has been recorded from primary forest, logged and cultivated areas. Chey (1994) found it generally frequent in softwood plantations in the lowlands of Sabah. The highest record is from 250m.

Biology

Kuroko & Lewvanich (1993) recorded Durio (Bombacaceae) and Nephelium(Sapindaceae) as host plants, the larvae feeding on young foliage.

Genitalia: