Calligrapha californica are small (5-8mm) Chrysomelidae (leaf beetles) that, in their native habitat within our region, are primarily associated with Bidens spp. (shown here on Bidens cernua) and Coreopsis tinctoria, both of which are wetlands plants.
As their native habitat has declined, and their range has expanded, they have been found on several other species of Asteraceae, and they can be a real pest species for gardeners trying to grow Coreopsis cultivars.
Eggs are deposited near the base of the host species in late summer. Those eggs overwinter and hatch in the spring. Larvae pupate in mid summer, and emerge shortly thereafter as adults, which persist until the first frosts. Both larvae and adults consume the leaves of the host plant. Tickseed Leaf Beetles can be found region wide. Calligrapha references the fact that many species in this genus have intricate patterns on their elytra.
Habitat- Historically, wetlands where their host plants grow. But can now be found almost anywhere.
Range- Region wide
Eats- Both larvae and adults prefer Bidens spp. and Coreopsis spp.
Flight Season- Mid summer into fall.