Identification
Adults: Upperside is light-to-blackish brown with forewings blacker above than forewings of Grizzled Skipper (P. centaureae); forewing has squarish white spots; hindwing usually has 2 rows of white spots which are more clearly defined than in P. centaureae. Underside is gray or slightly richer brown than P. centaureae, with dull spots that are often obscure. Male has a costal fold enclosing scent scales on the forewing.
Range
Inconspicuous, usually local and uncommon. Flies in the northwestern U.S. reaching to southern California, Arizona, and New Mexico. Flies in Canada reaching only in Alberta north to Nordegg, southern British Columbia north to Yoho National Park, and on southern and central Vancouver Island.
Habitat
Forest clearings, meadows, pastures, streamsides; from sea level to 10,000 feet.
Season
One brood from April-July.
Food
Caterpillar hosts: Herbaceous plants in the rose family (Rosaceae) including Drummond's potentilla (Potentilla drummondii), dusky horkelia (Horkelia fusca), Santa Rosa horkelia (H. tenuiloba), Cleveland's horkelia (H. bolanderi clevelandii), and probably others.
Adults take flower nectar.
Life Cycle
To find receptive females, males patrol and sometimes perch close to the ground in valley bottoms or swales. Females lay eggs singly on the host plant. Caterpillars make a webbed leaf nest in which they live and feed.
