Julia Heliconian
Dryas iulia

Medium-sized butterfly with a wingspan up to 3-5/8 inches. The male is bright orange-brown with several small black spots near the tips of the forewing and a narrow black border on the outer edge of the hindwing. The female is a duller orange-brown, with a black band across the forewing and more black markings. The underside of the hindwing in both sexes has a pale band through the center. The caterpillar has an orange head with black patches and two black horns on top. The body is usually brown or black with white patches and many long, black, needlelike spines arranged in rows. Some populations have white bodies with dark markings. The chrysalis is brown with a few silver markings.
South Florida and southern Texas; West Indies, Mexico, Central America and South America; strays to the north in the summer as far as Nebraska and coastal areas of Georgia and South Carolina.
Distribution and Abundance in Florida:
Locally common all year in South Florida; common all year in the Keys. Caterpillars are present all year.
Hammock edges, pinelands and open, disturbed sites.
Three or more broods per year. The elongated yellow eggs are laid singly on the new growth of host plants. Females will reject plants on which eggs have already been laid.
Natural History:
These butterflies are fast fliers, but have weak wingbeats. They "trap-line" by visiting the same flowers in sequence repeatedly during a single day or on several sequential days. Ants attracted by nectar glands on the leaves of host plants may eat the eggs or young caterpillars. Some host plants may develop structures that resemble eggs, which may cause females to avoid them.
Caterpillars feed on the leaves of host plants. Larval host plants include the native vines corkystem passionflower (Passiflora suberosa), maypop (Passiflora incarnata) and whiteflower passionflower (Passiflora multiflora var. multiflora) and the naturalized passion fruit (Passifora edulis). Native nectar plants include trees such as poisonwood (Metopium toxiferum), seagrape (Coccoloba uvifera) and smooth strongback (Bourreria succulenta); shrubs such as baycedar (Suriana maritima), common snowberry (Chiococca alba), shiny-leaved wild coffee (Psycotria nervosa), wild-sage (Lantana involucrata); wildflowers such as blue porterweed (Stachytarpheta jamaicensis), narrowleaf yellowtops (Flaveria linearis) and snow squarestem (Melanthera nivea); and vines such as yellowroot (Morinda royoc). Weedy native nectar plants include jack-in-the-bush (Chromolaena odorata), sleepy morning (Waltheria indica) and Spanish-needles (Bidens alba var. radiata). Adults also will feed on the invasive shrubs latherleaf (Colubrina asiatica) and shrubverbena (Lantana camara).
Some people may develop a rash after handling caterpillars. For more information, visit the Florida Museum of Natural History's Florida Wildflowers & Butterflies website and Butterflies and Moths of North America.

Erin Backus
Erin Backus
Erin Backus
Beryn Harty, 2012
Beryn Harty, 2012
Beryn Harty