Pleurobranchaea californica MacFarland, 1966

Description

The side-gilled sea slug Pleurobranchaea californica is a large, soft-bodied sea slug of the northeastern Pacific that can exceed 20 cm in length. The body is soft and flattened, yellowish-brown to tan with a network of darker markings. A large fleshy mantle covers the body, and a feathery gill projects from beneath its right edge. The front of the head bears a broad, veil-like flap whose margin senses the scent of prey. A thin, reduced internal shell is present.

Distribution

Found along the Pacific coast of North America from Port Orford, Oregon, to San Diego, California. It lives on sand and mud bottoms at depths of about 3–400 m.

Etymology

The specific epithet californica means "of California", after the region where it occurs.

Remarks

A voracious predator, it feeds on a wide range of invertebrates and small fish and will even eat other individuals of its own species. Because of its relatively simple and accessible nervous system, it has been widely used in neuroscience as a model for studying the neural basis of feeding behaviour, learning, and decision-making.

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References

• Pleurobranchaea californica n.sp., MacFarland F.M. (1966). Studies of opisthobranchiate mollusks of the Pacific coast of North America. Memoirs of the California Academy of Sciences, 6: 1-546, pls. 1-72.
• Pleurobranchaea californica, Behrens D.W., Hermosillo A., Fletcher K. & Jensen G.C. (2022). Nudibranchs & Sea Slugs of the Eastern Pacific. Molamarine.