Species · GBIF taxon 1937816
Black Swallowtail Caterpillar
Papilio polyxenesAlso known as Parsleyworm, Eastern Black Swallowtail Caterpillar, Parsnip Swallowtail Caterpillar, American Swallowtail Caterpillar
These striking caterpillars sport bright green bodies banded with black and dotted with yellow or orange spots, warning predators of their foul taste. When threatened, they deploy a bright orange, Y-shaped gland called an osmeterium from behind their head, releasing a pungent, chemical odor. They are voracious feeders on plants in the carrot family, found munching on backyard dill, parsley, and fennel.
HerbivorousColorfulMetamorphosing
- diet
- Leaves of parsley, dill, fennel, carrots, and other Apiaceae plants
- family
- Papilionidae
- threats
- Pesticide use, habitat loss, and predatory wasps
- life Span
- 3 to 4 weeks as a caterpillar before pupating
LC
Safe to observe at a normal distance.
- Gently provoke to see the osmeterium: Lightly touch the caterpillar's head to watch it deploy its bright orange, foul-smelling defensive horns.
- Provide host plants: Grow dill, parsley, or fennel in sunny garden spots to attract egg-laying adult females.
- Handle with care: Transfer caterpillars gently using a leaf or stem rather than picking them up directly.