Butterflies on San Bruno Mountain

The Western Tiger Swallowtail (Papilio rutulus) is a common swallowtail butterfly of western North America, frequently seen in urban parks and gardens as well as in rural woodlands and riparian areas. It is a member of the Papilio genus, of which Papilio appalachiensis and Papilio xuthus are also members. It is a large, brightly colored and active butterfly, rarely seen at rest; its wingspan is 7 to 10 cm (~2.75 to 4 in), and its wings are yellow... less ↑

The Pipevine Swallowtail or Blue Swallowtail (Battus philenor) is a swallowtail butterfly found in North America and Central America. The butterflies are black with iridescent blue hind wings. They are found in many different habitats, but are most commonly found in forests. The black or red caterpillars feed on Aristolochia species, making them poisonous as both larvae and adults, while the adults feed on the nectar of a variety of flowers. less ↑

The Anise Swallowtail, Papilio zelicaon, is a common swallowtail butterfly of western North America. Both the upper and lower sides of its wings are black, but the upper wing has a broad yellow stripe across it, which gives the butterfly an overall yellow appearance. There are striking blue spots on the rear edge of the rear wing, and the characteristic tails of the swallowtails. Its wingspan is 7–9 cm. Its body is somewhat shorter than the rather... less ↑

The Pale Swallowtail or Pallid Swallowtail (Papilio eurymedon) is a relatively common swallowtail butterfly found throughout much of the western United States. It is found on the Pacific coast from northern Baja California to southernmost British Columbia and inland to New Mexico and the Black Hills of South Dakota. It is present from the coast to western Montana and Wyoming to northern New Mexico. It is absent from most of Nevada and western Utah. It prefers... less ↑

Battus philenor hirsuta, the California pipevine swallowtail, or hairy pipevine swallowtail, is a subspecies of the pipevine swallowtail that is endemic to Northern California. Populations are found throughout the Sacramento Valley and outside of the valley in Contra Costa and Alameda Counties. The butterfly is black with hind wings that have iridescent green-blue coloring above and a row of red spots below; the caterpillars are black with fleshy protrusions and red spots. The subspecies' butteflies are... less ↑