Monarch caterpillar (monarch larva)

Milkweed plants in meadows, prairies, gardens, roadsides, and other open habitats throughout the Americas. Larvae remain on or near milkweed.

Feeds almost exclusively on milkweeds (Asclepias species), consuming leaves and occasionally flowers. Milkweed toxins are sequestered in its body.

Passes through five larval instars, molting between each, then forms a chrysalis and emerges as an adult butterfly. Its conspicuous stripes and paired filaments advertise chemical defenses; it may drop or thrash when disturbed.

Harmless to people when handled normally, though milkweed compounds make it unsuitable for ingestion. It is an important pollinator as an adult and a major prey item despite its defenses; monarch populations face habitat loss and pesticide exposure.