Cerberilla pungoarena was located on sandy substrate at a depth of 55 feet. Lengths were 2 cm. Water temperature was 52 degrees F.

There are two animals in this image. The genital mass of each is protruding and the individual on the left is depositing a white line of substance on the dorsum of the right individual. I hypothesize that this is ovoposition (egg laying). The other individual proceeded to reciprocate the behavior.