Mead's Sulphur (Colias meadii W. H. Edwards)
Wing span: 1 1/2 - 2 inches (3.8 - 5.1 cm).
Identification: Upperside of male deep reddish orange with wide, dull black border; female lighter orange, border containing orange spots. Underside of both sexes greenish-yellow, with hindwing white spot circled in red.
Life history: Males patrol open tundra for females. Females lay eggs singly on host plant leaves, which are then eaten by the caterpillars. Third-stage caterpillars overwinter.
Flight: One flight from July-August.
Caterpillar hosts: Plants in the pea family (Fabaceae) including clover (Trifolium) and Astragalus species.
Adult food: Flower nectar including alpine sunflower and asters.
Habitat: At or near treeline in high mountains, tundra, subalpine meadows.
Range: Restricted to the Rocky Mountains from Alberta south to Colorado.
