Io moth caterpillar

Woodlands, forest edges, gardens, and other areas with host plants across eastern and southern North America.

Larvae chew leaves of many plants, including willow, oak, maple, sweet gum, and grasses. Adults do not feed, living mainly to reproduce.

Gregarious early instars may feed in groups; mature caterpillars often become more solitary. Their branched spines deliver venom, and adults emerge as large, nocturnal moths with prominent eyespots.

Contact with the spines can cause painful, burning dermatitis, so avoid handling. They are native herbivores and serve as prey for birds and other predators.