Colias behrii, the Behr's Sulphur or Sierra Green Sulfur, is a butterfly

Butterfly

A butterfly is a mainly day-flying insect of the order Lepidoptera, which includes the butterflies and moths. Like other holometabolous insects, the butterfly's life cycle consists of four parts: egg, larva, pupa and adult. Most species are diurnal. Butterflies have large, often brightly coloured...

 in the Pieridae

Pieridae

The Pieridae are a large family of butterflies with about 76 genera containing approximately 1,100 species, mostly from tropical Africa and Asia. Most pierid butterflies are white, yellow or orange in coloration, often with black spots...

 family. It is endemic to California

California

California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

's Sierra Nevada from Tuolumne County south to Tulare County.

The wingspan

Wingspan

The wingspan of an airplane or a bird, is the distance from one wingtip to the other wingtip. For example, the Boeing 777 has a wingspan of about ; and a Wandering Albatross caught in 1965 had a wingspan of , the official record for a living bird.The term wingspan, more technically extent, is...

 is 35 millimetre. The upper surface of the males is dull green with a dark border and with a pale hindwing cell spot. Females are greenish-yellow with a dark diffuse border. The underside of both sexes is green. Adults are on wing from July to August.. They feed on flower nectar.

The larvae feed on Vaccinium

Vaccinium

Vaccinium is a genus of shrubs or dwarf shrubs in the plant Family Ericaceae. The fruit of many species are eaten by humans and some are of commercial importance, including the cranberry, blueberry, bilberry or whortleberry, lingonberry or cowberry, and huckleberry...

species and Gentiana newberryi

Gentiana newberryi

Gentiana newberryi is a species of gentian known by the common names alpine gentian and Newberry's gentian.It is native to the high mountains of California and Oregon, and its range just extends into Nevada. This is a small perennial herb growing short stems which lie against the ground or snake...

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