Diet

• The larvae of Battus polydamas feed almost exclusively on plants in the birthwort family (Aristolochiaceae).

• The caterpillars sequester aristolochic acids from their host plants, which contribute to their chemical defence against predators.

Habitat

• Caterpillars occur wherever suitable Aristolochia vines are established, including tropical forest, dry forest, woodland edges, clearings, gardens and disturbed vegetation.

• They may feed on vines growing in open vegetation as well as those climbing through shrubs and trees.

• In tropical regions, the larvae can occur in both relatively undisturbed forest and human-modified habitats where suitable host plants are present.

Description

• The mature caterpillar is generally dark brown to black, with conspicuous fleshy tubercles distributed along the body.

• The tubercles are relatively short compared with those of some related swallowtail larvae and may be reddish, orange or dark in colour.

• Early instars are smaller and less strongly marked, becoming increasingly dark and conspicuous as they mature.

• The caterpillars retain chemical compounds from Aristolochia, making them distasteful and providing an important defence against predators.