What is the black swallowtail caterpillar called?

'The parsley caterpillar' is what the black swallowtail [Papilio polyxenes] caterpillar is called. That's because its main, preferred food source is parsley [Petroselinumspp]. 'Plan B' food sources include other members of the carrot family Apiaceae: dill [Anethum graveolens], fennel [Foeniculum vulgare], and Queen Anne's lace [Daucus carota].

Butterfly caterpillars tend not to be the voracious feeders that moth caterpillars may be. But gardeners may or may not find even controlled feeding unattractive and upsetting. For example, those who see Queen Anne's lace as weed and not as a source of beautiful pressed flowers may be huge fans of the parsley caterpillar!