The ceanothus silk moth (Hyalophora euryalus) is found in woodlands and forest from British Columbia to western Montana and south to Baja California.
The ceanothus silk moth color varies – rose red, purple red or dark red-brown. The fore wings have a large, white, comma-shaped spot and a round black spot on the apex. An elongated white spot on the hind wings helps in identification.
Ceanothus silk moth caterpillars (larvae) are green with orange thoracic tubercules and white abdominal tubercules. They feed on a variety of host plants including bitterbrush, snowbush, madrone, gooseberry, alder and mountain mahogany.
The adults of this species are nocturnal and fly in the spring. They do not feed.
I photographed this ceanothus silk moth on the door of the Lookout Volunteer Fire Department on Juniper Drive in Lookout CA.