Wing span: 2 3/4 - 5 inches (7 - 13 cm). 

Identification: Upper surface of hindwing iridescent blue or blue-green. Underside of hindwing with submarginal row of 7 round orange spots in iridescent blue field. 

Life history: Adult males patrol likely habitat in search of receptive females. Females lay batches of eggs on underside of host plant leaves. Caterpillars feed in small groups when young but become solitary when older.
Wintering is by the chrysalis. 

Flight: In the East and California, adults fly primarily in late spring and summer, but the butterfly is commoner in late summer and fall in the South and Southwest. Where lack of freezing temperatures permit, adults may fly
continuously. In lowland tropical Mexico they may be found in any month. 

Caterpillar hosts: Pipevines (Aristolochia species), including Aristolochia californica, A. serpentaria and others. 

Adult food: Solely nectar from flowers including thistles (Cirsium species), bergamot, lilac, viper's bugloss, common azaleas, phlox, teasel, azaleas, dame's-rocket, lantana, petunias, verbenas, lupines, yellow star thistle,
California buckeye, yerba santa, brodiaeas, and gilias.  Habitat: A wide variety of open habitats, open woodland, and woodland edges. 

The Pipevine swallowtail (3.0-4.5") ranges from southern New England westward to the pacific Coast and southward into Mexico.