Spanish Dancer

Hexabranchus sanguineus is a large dorid nudibranch which commonly grows up to a maximum length of 25 cm, with some reports to 40 cm in the Red Sea.

All Hexabranchus species have soft, flattened bodies, the anterior dorsal portion has a pair of retractable rhinophores and the posterior part has six contractile gills inserted independently in the body. The pair of oral tentacles are constituted by a fine flexible membrane provided with large digital lobes.

In a normal situation when the animal is crawling, the edges of its mantle are curled upwards creating a peripheral blister. If the animal is disturbed, it unfolds its edges and can swim through contractions and undulations of the body to move away from the disturbing element. Its common name, Spanish dancer, comes from this particular defense.

This species is reported from the Red Sea, the Western Indian Ocean, French Polynesia and the Western Pacific, with different colour morphs in each region which are not differentiated by morphology or DNA barcodes.

It likes rocky and coral reefs with many sponges and shelters from 1 to 50 meters deep.