The common crow butterfly is a large black butterfly with white spots on the fore wings and a band of elongated spots on the hind wings. The outer wing margins have small white spots. The males have a pair of hidden orange-yellow brushes at the tip of the abdomen, which they can extend into bright coloured patch as part of the mating ritual or to deter predators. These brushes emit a musky odour. The caterpillars are striped. Pupa have metallic silvery sheen.