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Marine Animal Encyclopedia

Hermissenda Sea Slug Hermissenda crassicornis

The Hermissenda sea slug, usually known simply as Hermissenda, has an unusual way of deterring predators. It separates the stinging cells from any organism it eats and stores them in the orange-red tips of petal-like tentacles, or cerata, that cover its back. Any creature that touches the hermissenda's cerata is stung. Unlikely though it seems, Hermissenda is used extensively by scientists conducting memory experiments. The animal has an excellent sense of smell that enables it to find its way around mazes to locate food, and it can be “taught” to respond to simple stimuli.

Hermissenda Sea Slugzoom image
  • Class Gastropoda
  • Length Up to 3 in (8 cm)
  • Habitat Mud flats, rocky shores
  • Distribution Northwest and northeast Pacific
Hermissenda Sea Slug habitat mapzoom image