Cercyonis

Cercyonis oetus

A species of the Great Basin, East slope and alpine zone of the Sierra Nevada. On our transect resident on Basin and Castle Peaks above tree-line on volcanic substrates, and in sagebrush-bitterbrush shrub-steppe along the east edge of Sierra Valley. Flies jerkily over the top of the vegetation, but lands frequently. Not a frequent flower visitor, but comes to Mule's Ears and Sulphur Flower, and late in the season to Rabbitbrush.

Cercyonis pegala boopis

Our representative of a transcontinental, polytypic species, the Ox-Eyed Satyr is local and usually uncommon in our region. On the transect it occurs at Gates Canyon, where it seemingly colonized only quite recently, and at Sierra Valley and is unrecorded elsewhere. It generally occurs along or near streams in grassland or foothill woodland. Although it occasionally visits flowers-especially Canada Thistle at Sierra Valley-, it is usually seen flying with an odd, jerky motion among tall grasses; if disturbed it often seeks shelter inside brambles or other thickets.

Cercyonis sthenele silvestris

The currently-favored common name is misleading insofar as this species occurs widely in California west of the Great Basin. Like the other species of Cercyonis it is single-brooded, and the adults rather long-lived. On the transect it is abundant in grassland, shrub-steppe and alfalfa fields at Sierra Valley and occurs at lower density in brushy, rocky areas at Washington and Lang Crossing on the West slope. Adults fly low, near the ground, moving jerkily through the vegetation. They often sit on rocks or in paths but this is not territorial perching.