Gastrophora henricaria is a large and eye-catching moth. Females are occasionally seen perched in the undergrowth during the day, probably freshly emerged, and both sexes come readily to light where they often display the spectacular orange hindwing. If the forewing is covering the hindwing, a settled moth may permit a gentle separation of the wings without flying off. The brightly coloured hindwings are an excellent example of “startle” colouration. In suddenly exposing the hindwing when threatened, the moth causes a vertebrate predator to hesitate, buying time to escape. The males have bushy branched antennae, while the females have narrowly branched antennae and a broad egg-carrying abdomen. Both sexes have a large ink coloured blotch on the underside of the forewings. Gastrophora henricaria is often encountered in lowland ACT including suburban areas. It is widespread in southeastern Australia and flies in spring and early summer. Its larvae feed on Eucalyptus and Lophostemon.