Monkey-slug
Guides
Phobetron
hag moth, monkey slug
Phobetron is a genus of slug caterpillar moths in the family Limacodidae, containing at least four described species distributed across North, Central, and South America. The genus is notable for its distinctive caterpillars, commonly called "monkey slugs" or "hag moths," which possess stinging urticating spines concealed beneath a cloak of hair-like setae. These caterpillars are polyphagous and feed on a wide range of woody and herbaceous plants. The genus includes the well-known species Phobetron pithecium, whose caterpillar is frequently encountered in eastern North America.
Phobetron pithecium
Hag Moth, Monkey Slug (larva)
Phobetron pithecium, commonly known as the hag moth, is a species of slug caterpillar moth in the family Limacodidae. Its larva, called the monkey slug, is one of the most distinctive caterpillars in North America, bearing nine pairs of curly, hair-covered projections that give it an appearance resembling a shed spider skin or leaf debris. The species occurs across eastern North America from southern Canada to the Gulf Coast, with adults active primarily in summer. Both larva and adult exhibit notable defensive adaptations: the caterpillar's tubercles can detach without harm to the animal, and adults display sexual dimorphism with males having translucent wings while females are drab brown with yellow leg scales and reportedly mimic bees.