The border eventually fades to yellow on museum specimens. The maculations are fused on some males, more closely resembling the nominate subspecies.
Antennae are about as long as the body or shorter.
Body length is about 13-21 mm. Females are more robust, elytra are subparallel, and the dark pattern is not reduced. Antennae reach to about the middle of the elytra and body length is about 18-25 mm. Both sexes of valley elderberry longhorn beetles are readily identified due to their distinctive appearance. Date 13 MAR 96 maculations resemble the nominate subspecies, Desmocerus californicus californicus Horn, 1881.