Butterflies of Sri Lanka-Tawny Coster

Tawny Coster

Acraea terpsicoreThe Tawny Coster (Acraea terpsicore) is a small leathery winged butterfly which is common in grassland and scrub habitats. It belongs to the Nymphalidae or brush-footed butterfly family. It has a weak fluttery flight. It is avoided by most insect predators.
Male: Upperside tawny. Fore wing: a transverse black spot in cell, and another irregular, oblique and broader at the disco-cellulars ; a discal series of spots in interspaces 1, 3, 4, 5, 6 and 10, and the apex and termen black. The upper four spots of the discal series inclined obliquely outwards, the lower two obliquely inwards ; the black edging to apex and termen narrowing posteriorly, but with slender linear-projections inwards in the interspaces. Hind wing: a basal series of four or five black spots with a similar spot beyond in middle of cell and a subcostal black spot above it, followed by a discal series of obscure blackish spots and a minute postdiscal black dot in interspaces 4 and 6 respectively ; finally, a broad black terminal band medially traversed by a series of small spots of the ground-colour. Most of the macular black markings are obscure, being only the spots on the underside seen by the transparency of the wing-membrane ; the inner edge of the black terminal band crenulate.
Underside: ground-colour ochraceous yellow or a paler tawny yellow. Fore wing paling to whitish on the apex, with the black markings as on the upper side but somewhat blurred and diffuse. Hind wing: the black spots and black terminal band as on the upperside, but the spots more clearly defined, none obscure; the series of spots traversing the black terminal margin very much larger and white- not tawny ; the base of the wing black, separated from the basal transverse series of black spots by two or three large whitish spots. Antennae black, head and thorax black spotted with ochraceous and white ; Abdomen anteriorly black, posteriorly ochraceous yellow with narrow transverse black lines; beneath, the palpi, thorax and abdomen ochraceous, the thorax spotted with ochraceous, the abdomen with a longitudinal line of black at base.

Female: Similar to that of the male. Upperside: ground-colour duller; the black spots on fore and hind wings larger, the upper discal spots often coalescing and forming an irregular oblique short band; the black edging to apex and termen on the fore wing and the black terminal band on the hind wing proportionately broader, the spots traversing the latter larger and whitish.
Underside: ground-colour much paler and duller, markings as on the upperside and, as in the male, the spots on the hind wing better defined than on the upperside, Antennae, bead, thorax and abdomen as in the male.
Wing expanse of 53–64 mm.