Trirhabda flavolimbata, family Chrysomelidae, Leaf Beetles
Subfamily Galerucinae, Skeletonizing Leaf Beetles
Genus Trirhabda
Species: need to ID host plant to be sure:
* T. flavolimbata: host plant Coyote Brush (or Bush, Baccharis pilularis),
* T. luteocincta: host plant California Sagebrush (Artemesia californica), and
* T. didacta: host plant Yerba Santa (Eriodictyon californicum).
This one was on Coyote Brush, so we'll call it T. flavolimbata