Western Square-dotted Blue (Euphilotes battoides)
Mt. Hood, Clackamas Co., OR 8/7/06.
These tiny but spectacular butterflies feed on (as caterpillars) and also nectar on various Eriogonum species. This one is on Eriogonum umbellatum (Sulphur-flowered Buckwheat), which is the most abundant species on Mt. Hood.
Each high volcano in Oregon has an isolated population of this species, differing slightly from the one on the next volcano. Square-spotted Blue may be a complex of related species.
Mt. Hood, Clackamas Co., OR 8/8/06.