Opalescent Nudibranch

Hermissenda crassicornis

Opalescent Nudibranch

Hermissenda crassicornis

Other Common Names
Opalescent sea slug, Thick horned nudibranch

Rocky Coast

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

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Since opening in 1992, the Oregon Coast Aquarium has been a premier attraction on Oregon’s central coast and an enduring advocate for the health of our ocean. For over three decades this 501(c)3 non-profit organization has supported marine wildlife and fostered environmental stewardship through its education programs, community partnerships, and rehabilitation efforts. Accredited by the Association of Zoos & Aquariums, the Oregon Coast Aquarium is consistently ranked as one of the top 10 aquariums in the U.S., providing visitors with opportunities to connect with 15,000 animals spanning 300 different species. The Oregon Coast Aquarium is located at 2820 S.E. Ferry Slip Rd., Newport, OR. Learn more about the Oregon Coast Aquarium and its vital work at aquarium.org, 541-867-3474. Follow us on Facebook or Twitter for the latest updates.

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