California Berthella

White Berthella

Berthella californica

Physical Description

The California Berthella, Berthella californica, resembles nudibranchs but belongs to the pleurobranchs or side-gilled opisthobranchs. It features a large gill positioned along the right side of the foot under the overhanging mantle. Its rhinophores are rolled, and it has a thin white line along the edge of the dorsal mantle, which can vary from translucent white to brown and may have scattered white dots. Berthella californica can reach up to 2 inches in length.

Habitat and Geographical Range

Found along the eastern Pacific coast, from Alaska to Baja California, the California Berthella inhabits coastal waters and rocky substrates. It prefers intertidal and subtidal zones, where it can find suitable prey and breeding sites.

What They Eat and How They Breed

California Berthellas primarily feed on various invertebrates such as sea squirts and occasionally on fish. As hermaphrodites, they lay fertilized eggs in egg ribbons, where they develop into larvae. After several weeks, the larvae are released into the water to complete their development and settle onto the seabed.

Similar Nudibranchs

There are several species of white dorid nudibranchs found in Monterey. For species often mistaken for the White Berthella, check out these links.

Other Species