Colias tyche

Hostplant: Astragalus alpinus. The larva also accepted Astragalus glycyphyllos in captivity. I started out using A.alpinus and changed over to A.glycyphyllos later without any problems. A few sources online mentions Vaccinium uliginosum as a possible hostplant. The adult female did not want to lay any eggs on it, and the larva did not accept it.

Lifecycle and behavior: The female easily laid eggs on fresh hostplant. As with Colias hecla, the eggs changed color from yellow to red during development. The eggs used 5-6 days to hatch. The larva seemed to prefer eating the leaves of the hostplant through its development, but did also eat the flowers and seedpods. The larval stages lasted 3,5-4 weeks, and it molted 4 times. The pupal stage lasted a week. In the wild the larva hibernates at least once, and it can hibernate a second time as pupa. In my breeding, one larva went all the way to adult the same year. The rest of the larva hibernated as full-grown L5. After hibernation, the larva pupated right away.

The butterfly is an arctic species confined to the 3 northern most states in Norway. Depending on the weather, it’s usually on the wing from late June through July.

Note: The Scandinavian populations are regarded as ssp. werdandi.