Crested Aeolis

Overview

The crested aeolis (Antiopella cristata) is a semi-transparent, oval-shaped nudibranch known for its distinctive, swollen cerata that cover its back and head. A unique identifying feature of this species is the caruncle, a sensory, cockscomb-like structure located between its rhinophores.

Appearance

This species typically displays a cream, light brown, or milky-white body, sometimes with orange tints. Its numerous cerata are smooth and inflated, each containing a thin, dark, branching digestive gland visible through the translucent surface. The tips of these cerata are marked with iridescent, bluish-white pigment, which is also found in patches along the back and head. The rhinophores are lamellate and prominent, often appearing to have spiral grooves.

Distribution & habitat

Antiopella cristata is found in the Northeast Atlantic, ranging from Norway down to Morocco, and throughout the Mediterranean Sea. It prefers shallow, sheltered rocky environments, where it is often found on or near its primary food sources.

Feeding

This nudibranch feeds on various erect, tufted bryozoans, including species such as Bugula, Cellaria, and Bicellariella. Unlike many other nudibranchs, it does not sequester stinging cells from its prey.

Biology & behavior

This species is a fragile, slow-moving mollusc often found in calm, shallow waters. When threatened or disturbed, it may autotomize (shed) its cerata as a defensive measure. It is known to host the ectoparasitic copepod Doridicola agilis. Spawning typically occurs from April through September, with additional activity recorded in December; the eggs are laid in a wavy, circular, bead-like string.