Flabellinopsis iodinea (J. G. Cooper, 1863)

Description

A striking aeolid with a vivid purple body, orange cerata arranged in clusters along the back, and scarlet rhinophores and oral tentacles — a bold three-colour contrast. It grows to about 70 mm. Remarkably, all three colours are produced by a single diet-derived pigment (astaxanthin) held in three different states. When threatened, it can swim away by flexing its body strongly from side to side.

Distribution

Northeastern Pacific, from British Columbia, Canada, south to southern Baja California Sur, Mexico, the Gulf of California, and the Galápagos Islands. It occurs on rocky bottoms from the intertidal zone to about 40 m depth. The species was originally described from California.

Etymology

The specific epithet iodinea means “violet-coloured” (from Greek iodes), after the animal’s brilliant purple body.

Remarks

A hydroid feeder, preying on Eudendrium (especially Eudendrium ramosum). It takes up the hydroid’s stinging cells and stores them in the tips of its cerata for its own defence. Popularly known as the “Spanish shawl,” it is one of the most spectacular aeolids of the North American Pacific coast.

---

References

• Aeolis iodinea n.sp., Cooper J.G. (1863). On some new genera and species of California Mollusca. Proceedings of the California Academy of Natural Sciences. Series 1, 2: 202-207.
• Flabellina iodinea, Helmut Debelius, Rudie H. Kuiter. (2007). Nudibranchs of the World.
• Flabellinopsis iodinea, Korshunova T., Martynov A., Bakken T., Evertsen J., Fletcher K., Mudianta I.W., Saito H., Lundin K., Schrödl M. & Picton B. (2017). Polyphyly of the traditional family Flabellinidae affects a major group of Nudibranchia: aeolidacean taxonomic reassessment with descriptions of several new families, genera, and species (Mollusca, Gastropoda). ZooKeys. 717: 1-139. https://doi.org/10.3897/zookeys.717.21885