About Colias scudderi Reakirt, 1865
Colias scudderi Reakirt, 1865 (also referenced as Colias scudderii), commonly called the willow sulphur, is a butterfly species belonging to the family Pieridae. This butterfly is distributed from Alaska southward through the Rocky Mountains to northern New Mexico. Its typical habitats include mountain meadows and willow bogs. The wingspan of adult willow sulphurs measures 38–51 mm, which equals 1.5–2.0 inches. Adults are active and in flight from June through August. Adult willow sulphurs feed on flower nectar. The larvae of this species feed on the leaves of Salix plant species, specifically including Salix reticulata, Salix lutea, and Salix planifolia. The second, third, and fourth instar larvae of Colias scudderi hibernate over winter.
