Melissa's Blue on a flower

Western Colorado Insects

Melissa's Blue

Plebejus melissa

Melissa's Blue Larvae

Larvae of Melissa's blue butterfly are commonly found in seed production plots of Hedysarum boreale. They can also be expected to be found on species of Lupinus, Astragalus, Glycyrrhiza, Lotus, and Medicago.

Larvae are green in color, with a slightly fuzzy texture. They are about 1/4" long when mature. They will feed on foliage and seed pods. While larvae can be abundant, we have not observed significant damage although it certainly is a possibility if populations get extremely high.

Larvae are often tended by ants who protect them from predators. The ants feed on a sugary secretion from the caterpillar as "payment" for their protective services.

Melissa's Blue Larvae Dorsal View
Melissa's Blue Pupa Pupa are present in the soil or residue on the soil surface. They are about 5/16" long, green in color, and with out any cocoon. The pupa stage probably lasts a week or less during the summer generation.

Melissa's Blue

Male and female Melissa's Blue are dimorphic. Males are blue on the upper side with a narrow dark border. Females have a continuous row of submarginal reddish-orange spots on the upper side. Both species have a submarginal row reddish-orange spots on the underside.

Eggs are laid on assorted plant parts of the host plant or nearby debris.

There are two or three broads annually depending on elevation.

Melissa's Blue
Melissa's Blues Mating

This page was updated on April 26, 2014