The Gulf Fritillary or Passion Butterfly (Agraulis vanillae) is a bright orange butterfly of the family Nymphalidae and subfamily Heliconiinae. It was formerly classified in a separate family, the Heliconiidae or longwing butterflies, and like other longwings this species does have long, rather narrow wings in comparison with other butterflies. It is not closely related to the true fritillaries. It is the only member of genus Agraulis.
Agraulis vanillae is a year-round resident in a few small regions of the United States, including Calif., southern Tex. and southern Fla. It is migratory throughout much of the US (Scott 1986), and ranges south to Argentina, and the Antilles and Bahamas. Habitats are forest margins, fields, scrub, suburbs. Host plants are usually vines, and include many species restricted to one genus Passiflora (Passifloraceae). Eggs are laid on the host plant singly. There are multiple flights, year round in s. Tex., s. Fla, and s. Calif (Scott 1986). Considered synonymous with Dione vanillae by some sources (Scott 1986).