Opalescent Nudibranch

Hermissenda crassicornis

Opalescent Nudibranch

Hermissenda crassicornis
Other Common Names
Opalescent sea slug, Thick horned nudibranch
Other Common Names
Opalescent sea slug, Thick horned nudibranch

At the Aquarium

Rocky Coast

Appearance

This small sea slug has a white body, orange stripe on its head, and vivid orange cerata running down its back.

Habitat

Tide pools, bays and estuaries

Diet

Tunicates, small cnidarian polyps

Life History

Every opalescent nudibranch can both produce eggs and fertilize the eggs of others. After two nudibranchs pair up, each one lays a ribbon-shaped spiral of eggs.

IUCN Status

Not Evaluated

Ecosystem & Cultural Importance

Opalescent nudibranchs–like all nudibranchs–play an important role in tidepools ecosystems!
Northern California to Alaska
These small sea slugs can be found in tide pools, estuaries and bays up and down the Oregon coastline.
Eating small cnidarians allows this nudibranch to steal the stinging cells and use it for self defense.

Citations & Other Resources

  • Megina, Cesar & Gosliner, Terrence & Cervera, Juan Lucas. (2007). The use of trophic resources by a generalist eolid nudibranch: Hermissenda crassicornis (Mollusca: Gastropoda). Cahiers de biologie marine. 48. 1-7.
  • Lindsay T, Valdés Á (2016) The Model Organism Hermissenda crassicornis (Gastropoda: Heterobranchia) Is a Species Complex. PLoS ONE 11(4): e0154265. https://doi.org/10.1371/journal.pone.0154265