Caterpillars are warty, dark brown or greyish, with tufts of greyish hairs, an orange crossline on each segment, a wide whitish line along the back and two other lateral white lines.
This species in southern Europe overwinters as a caterpillar. Pupation occurs on the ground near the host plants, usually on fallen leaves and dead vegetation, or pieces of bark and old wood. During mild winters in temperate and typically Mediterranean climates this species hibernates as pupae. Adults of this multivoltine species usually are present from March to early November in three generations a year, but in the tropics, they develop continuously. They fly both day and night and come to light. The polyphagous larvae feed on a range of herbaceous plants, mainly on forget-me-not (Myosotis), Echium, Borago officinalis, Solanum, Plantago lanceolata and Anchusa species. In the Afrotropical realm they mainly feed on Trichodesma zeylanicum, Lithospermum, Heliotropium, Trichodesma and Gossypium species.
Due to their food, the caterpillars accumulate a large amount of alkaloids, consequently also the moths are toxic and unpalatable to birds. The characteristic colouration of its wings serve as a sign of warning to their predators (aposematism).