Papilio polyxenes – Black Swallowtail

Caterpillar food: plants in the Umbelliferae – the carrot family – including Queen Anne’s Lace, Parsley, Dill as well as native plants in that family.

Male Black Swallowtail – 9/2010  Males have larger yellow markings, and less blue.


Male – underside of wings


Females have less yellow and more blue, but the same basic pattern.


A newly hatched female – underside of wings

I often see male Black Swallowtails “puddling” on our driveway during the summer – gathering up salts to use in mating.


A puddling male


When the females lay an egg, they hover next to the host plant – laying the egg without resting on the plant.


The eggs are laid singly – this one is on a dill leaf


Early instars are dark with a white band around the middle.  They look a bit like bird droppings – possibly for camouflage.


An older caterpillar – on Yellow Pimpernel (Taenidia integerrima)



Black Swallowtail caterpillar – late instar – on Wild Parsnip (Pastinaca sativa)



Two Black Swallowtails in their pre-pupa position


When caterpillars pupate, sometimes the chrysalis is green, sometimes brown.


5/6/2009  The adults are some of the earliest butterflies to emerge from their chrysalises in the spring.