Diagnosis. The male antennae are noded. The wings are browner in tone than in butesalis, concisalis and acutivalva, the shade of which grades darker into the submarginals distal to the postmedial on the forewing and over a similar distance on the hindwing. The dark postmedial and antemedial are crenulate, more emphatic than in macrotheca, the former sigmoid with its strongest curvature towards the costa and the latter gently and evenly curved, meeting the costa further basad than it does the dorsum. The male genitalia have broader valves than any of the three greyer species, and these have distinct processes from both the costa and the sacculus. The aedeagus vesica has a prominent distal diverticulum as in macrotheca, but it is broader with the coarse scobination consisting of shorter spines and being more restricted to the base of the diverticulum.
Taxonomic note. The species was reviewed and illustrated by Owada (1992), with a further diagnosis in Owada (1987) of pseudoniphona.
Geographical range. Borneo, Peninsular Malaysia, Thailand, India, Nepal, Taiwan, Japan.
Habitat preference. Bornean material is restricted to the holotype male, taken at 4350ft on G. Poi, probably in montane forest.
Biology. Sugi (1987) illustrated the larva. It is spindle-shaped, an ochreous fawn, finely speckled and irregularly reticulated with darker grey-brown, this colour forming a pair of fine, irregular longitudinal lines dorsolaterally. The spiracles are black. The larva feeds on dead leaves.
