Yellow-Spotted Cadlina

Cadlina flavomaculata

Cadlina flavomaculata is a colorful sea slug characterized by its ovate, translucent white mantle adorned with distinctive brown to black rhinophores. Each side of the mantle features a series of large yellow spots, which are mantle glands. Some individuals may also display a yellow border along the mantle, although this is not universal. The branchia, or gills, can range in color from white to yellow, and the species typically reaches a length of about 15 mm. This nudibranch is found in the northeastern Pacific, inhabiting both subtidal and intertidal zones from Vancouver Island down to the southern tip of Baja California. It is relatively rare overall but can be commonly observed at certain diving sites between Monterey, Carmel, and Big Sur. Most recorded sightings occur at depths shallower than 40 meters, with a significant number found below 30 meters. Cadlina flavomaculata primarily feeds on the sponge Aplysilla glacialis. As a simultaneous hermaphrodite, it engages in mating behavior where individuals may alternate roles as male and female. Eggs are laid on a substrate, developing into planktonic larvae before maturing into adults. Encounters with this species during dives can be intriguing, as divers may spot them resting on sponges or moving slowly along the substrate. The conservation status of Cadlina flavomaculata has not been evaluated, and it is noted as relatively rare in its distribution. Divers should be mindful of its habitat and the ecological role it plays in the marine environment.