Himantopterus Wesmael

Type species: Himantopterus fuscinervis Wesmael, Java, Peninsular Malaysia, Sumatra.

Synonym: Thymara Doubleday (type species zaida Doubleday, India).

The adults are small, with rounded forewings, the discal cell extended, the venation reduced, a series of veins running more or less in parallel from the cell to an oblique, extended distal margin. The hindwings are narrowed and extended into long tails (the venation being much reduced) that may be more than twice the length of the forewing (Plate 1, Moths of Borneo Volume 2). The head has prominent chaetosemata, but the mouthparts are reduced. The male antennae are bipectinate, those of the female biserrate.

The male genitalia of the Bornean species described below were illustrated in the original description. The uncus is mainly digitate but set on a broader base flanked by a pair of digitate socii (or double subuncus) about one third of the uncus length. The tegumen is broad but short. The valves are deep basally, simple, tapering to an acute apex. The aedeagus tapers from the base to a blunt apex; the vesica is a narrow tube, unornamented. This corresponds with the general description for the family by Epstein et al. in Kristensen (1998), who also stated that the female had an ovipositor that was not extensile, a slender ductus bursae and globular corpus bursae without a signum.

Barlow & Carter (1996) described the life history of the type species, as described above. The general features of the larva are described above. The larvae are defoliators, but swarm on the trunk of the host tree by day, ascending to feed in the crown by night. They eventually descend to pupate in a cocoon in the ground. The eclosed adults appeared to be extremely feeble and were not observed in flight. However, another species in Vietnam has been recorded in weak flight over a forest canopy (Owada et al., 2000).

The host plant was Shorea platyclados (Dipterocarpaceae).