Camponotus laevigatus
Camponotus laevigatus, formerly Camponotus quercicola, is a species of carpenter ant native to California. It nests in the dead branches of oaks such as Quercus wislizeni.
The more widespread ant formerly called C. laevigatus is now Camponotus laevissimus. According to AntWiki, "most literature as well as specimens in museums labelled as C. laevigatus actually refer to C. laevissimus."