Pseudonyctemera dissimulata Walker

Cyclosia dissimulata Walker, 1862, J. Proc. Linn. Soc. (Zool.), 6: 96.

Cyclosia ficta Walker, 1862, J. Proc. Linn. Soc. (Zool.), 6: 96.

Didina invaria Walker, [1865] 1864, List Specimens lepid. Insects Colln Br. Mus., 31: 123, syn. n.

Millieria pontioides Butler, 1881, Ann. Mag. Nat. Hist. (5), 7: 35.

Chalcosia analis Snellen, 1889, Tijdschr. Ent., 33: 307.

Chalcosia griseifusa Hampson, [1893] 1892, Fauna Br. India, Moths 1: 264, syn. n.

Pseudonyctemera pura Jordan, 1907, Gross-Schmett. Erde, 10: 28.

Pseudonyctemera minima Hering, 1922, Arch. Naturgesch., 88A (11): 49, 50.

Pseudonyctemera dissimulata Walker; Holloway, 1976: 91.

Diagnosis

This species shows marked sexual dimorphism. Males (the taxon minima is based on this sex) are much smaller, the forewings predominantly grey with some white delineation of the veins, and the hindwings predominantly white with some grey in the spaces at the margin. There is a semicircle of yellow at the centre of the hindwing dorsum on the underside. The larger females have the forewing more extensively white, with the veins delineated with a much darker grey that leads into more extensive grey shading in the marginal zone. The hindwings again are mostly white above, though the dark border of the underside shows through. The forewing underside resembles the upperside but the hindwings have a marginal blackish zone like the forewings, with the area basal to this extensively yellow. The female may mimic pierid butterflies in the genus Cepora Billberg (see also Cyclosia pieroides). Only females have been located for invaria, which is concluded to be just a variant of dissimulata as the pattern components are the same. However, the wings are more generally suffused with blackish grey on both surfaces. The hindwing above has its basal half paler, but the yellow of the same area on the underside is heavily suffused with black except for a diffuse area from the centre to two-thirds of the dorsum.

Geographical range

Peninsular Malaysia, Borneo, Sumatra, N. India, Burma.

Habitat preference

The species is frequent in forested and disturbed localities from the lowlands to about 1500m.

Genitalia: