Gabb's Checkerspot, Chlosyne gabbii, male

Note: consensus on BugGuide is that this is C. gabbii, but could almost as well be Northern Checkerspot, C. palla.

Shapiro does not list C. gabbii is a Bay Area species, but the location here is about 40 miles south of the bay, a
region where the ranges of the two species overlap and where, apparently various forms, possibly hybrids can be found.

Thus these two "Gabb's" could be Northerns -- needs further study.