South Florida has a very diverse population of butterflies, and one of the most interesting is the Giant Swallowtail butterfly (Papilio cresphontes). It is the largest species of butterfly found in North America. It has a wing span of 4-6.25 inches with a striking yellow and black coloration. The larva or caterpillar is sometimes referred to as The Orange Dog, because the host plant for this butterfly is members of the Citrus Family (Rutaceae). In S. Florida Citrus is still commonly grown, especially Key Limes, although several diseases have reduced the Citrus population. However, Citrus isn’t the only member of the family grown in S. Florida. Common Rue (Ruta graveolens), Wild Lime (Zanthoxylum fagara), White Sapote (Casimiroa edulis), and a small ornamental shrub, Lemonia (Ravenea spectabilis) are all members of the Citrus Family, and the Giant Swallowtail Butterfly will lay eggs on these plants for the larvae to consume.
The larvae or caterpillars resemble wet bird droppings when they hatch. This is a very useful camouflage to avoid predation. If this isn’t enough to avoid being eaten, they also possess an anatomical structure called an osmeteria. When the caterpillar is threatened, a pair of orange antennae like projections come out of the head emitting an unpleasant musky odor to ward off prey.
Richard Lyons Nursery carries many of the host plants for this butterfly as well as those for other butterflies which visit South Florida gardens.