This smallish carpenter ant was collected by Erik Brians, in Jamestown Ca, 10 March 2020.
Based on these photos, Dr. Philip Ward identified it as a small worker of Camponotus quercicola.
Here is a copy of the abstract of a paper, co-authored by Dr. Ward.
Systematics, Distribution, and Ecology of an Endemic California
Camponotus quercicola (Hymenoptera: Formicidae)
JURGEN GADAU, SEAN G. BRADY, AND PHILIP S. WARD
Department of Entomology and Center for Population Biology, University of California, Davis, CA 95616
Ann. Entomol. Soc. Am. 92(4): 514Ð522 (1999)
ABSTRACT The endemic California carpenter ant Camponotus quercicola Smith is a little known
component of oak woodland habitats containing Quercus wislizenii de Candolle and Q. agrifolia Nee.
Close investigation of one site, Stebbins Cold Canyon Reserve, showed that C. quercicola was a
dominant, arboreal ant species, foraging primarily at night. The 1st description of the sexual castes
of C. quercicola is provided, together with a guide to distinguish all castes ofC. quercicola from similar,
sympatric Camponotus species. We compiled a distribution map based on our own collections and
museum specimens. To test the phylogenetic position of C. quercicola within the North American
Camponotus sensu stricto group, we sequenced 385 bp of the mitochondrial gene cytochrome oxidase
I from 9 Camponotus species. C. quercicola did not form a clade with the North American C.
herculeanus species group to which it was previously assigned. Preliminary results of microsatellite
analysis suggested a polygynous colony structure in this species.