Facelinidae

Facelinidae is a family of colorful sea slugs, commonly known as aeolids, that belong to the order Nudibranchia. They are characterized by their prominent cerata, finger-like projections that cover their dorsal surface. These cerata serve a dual purpose: they act as respiratory organs and contain stinging nematocysts obtained from their prey, which they use for defense.

Doubtful Facelina – Facelina dubia

Facelina olivacea

Favorinus vitreus

Japanese Favorinus, Egg-Eating Nudibranch – Favorinus japonicus

Tsurunga Nudibranch, Ringed Favorinus – Favorinus tsuruganus

Nudibranch – Favorinus elenalexiae

Dicata Odhneri – Dicata odhneri

Sakuraeolis arcana

Nudibranch – Phidiana anulifera

Nudibranch – Pruvotfolia rhodopos

Next

Common Names

Facelinidae are commonly called aeolids, due to their distinctive cerata that resemble the mythical creature Aeolus, the guardian of the winds.

Characteristics

Facelinidae typically have elongated, slender bodies with a pair of rhinophores, sensory organs used for detecting food and navigating. They possess a radula, a ribbon-like structure with teeth that helps them scrape food. They are carnivores, primarily feeding on hydroids, which are colonial animals with stinging tentacles. Some species also feed on other cnidarians, including anemones and corals.

The most striking feature of Facelinidae is their bright and vibrant coloration. They often exhibit a range of colors, including red, orange, yellow, green, and blue, with contrasting patterns and markings. This coloration serves as a warning to potential predators, indicating their unpalatability due to the nematocysts they acquire from their prey.

Environments

Facelinidae are found in various marine habitats worldwide, inhabiting both shallow and deep waters. They are typically found in tropical and subtropical regions but can also be found in temperate waters. These sea slugs prefer environments with abundant hydroids, their primary food source.

References