Other Common Names
Orange Dog (larva in southern orange groves)
Synonyms and other taxonomic changes
Heraclides cresphontes--a split from genus Papilio
Adult: "Black with a yellow X on the front wing and basal and subapical bands on the hind wing. Usually easily distinguished from P. thoas by the lower three spots in the outer row on the front wing being much larger than the rest and running (at the top) into a distinct offset in the second row. [In P. thoas the lower four or five spots in the outer row are fairly even in size, tapering gradually down in size upward; not running into an offset in the second row at the third spot.]
Larva: brown or blackish with pale cream or whitish saddle in middle, and large cream patch on tail, imitating bird poop in coloration; when disturbed, extends orange-red osmeteria from behind head and emits sour unpleasant odor
Central America, Mexico, and across southern United States, northeastern US, and southern Ontario; strays north rarely to Nova Scotia, Quebec, Manitoba, and North Dakota
open woodlands and nearby fields, rocky and sandy hillsides near streams or gullies in the north; pine flats, towns, and citrus groves in the south
adults fly all year in the far south; two flights in the north from May to September
Larvae feed on leaves of plants in the Citrus family (Rutaceae), including Citrus (Citrusspecies), Pricklyash(Zanthoxylum species), Hoptree (Ptelea trifoliata), Rue (Ruta graveolens), etc. Adults take flower nectar from a variety of herbaceous plants and shrubs
eggs are laid singly on host leaves and twigs; at least two generations per year; overwinters in pupa stage inside a chrysalis
1. Egg. 2. Egg and first instar caterpillar. 3. Caterpillar. 4. Caterpillar in defensive posture. 5. Caterpillar ready to pupate. 6. Pupa. 7. Adult.
Often cited as the largest butterfly in the United States and Canada."(1)
However, the Two-tailed Swallowtail (Papilio multicaudata
) averages larger.
Thoas Swallowtail, Papilio thoas, has western distribution and smaller spots in lower outside leg of "X" on upperside of forewing
, - rare, S. Florida only) has narrower pale band.
pinned adult image
plus description, biology, larval and adult food, US distribution map (Butterflies and Skippers of North America, nearctica.com)
live images of all life stages
plus description, larval foodplants, distribution, flight season, habitat (Butterflies of Canada, CBIF)