Andy Coblentz

Acorn weevil – Curculio occidentis (Casey, 1897) (Coleoptera: Curculionidae).

Curculio occidentis is the most common acorn weevil in California and feeds on a variety of oaks and filberts. Adults are found throughout the summer feeding on fruits (pears, apples, peaches, etc.). Females drill holes into developing acorns to deposit their eggs. After a week or two, eggs hatch and the larvae spend several weeks eating the nut meat before chewing an exit hole in the acorn shell. They may overwinter in the acorn or drop to the ground and pupate in the soil nearby, ready to emerge the following summer. There has been some confusion regarding the scientific name of this species. Curculio uniformis (LeConte, 1857) is the earliest name for this species, but this name is preoccupied by another species, Curculio uniformis Marsham, 1802. The next available name is Curculio occidentis, (originally described as Balaninus occidentis by Casey in 1897), which is the currently accepted name. 

Back to Adopt A Drawer page

Andy Coblentz, an alumnus of UC Berkeley, has taken a keen interest in this species while sorting thousands of specimens at the California Academy of Sciences.

Learn more about our Adopt A Drawer program here