Facelina

Common Names

Facelina species are often referred to as "aeolids" or "aeolid nudibranchs." They are also known by more specific common names, such as the "orange-edged aeolid" (Facelina bostoniensis) or the "striped aeolid" (Facelina coronata), depending on the species.

Characteristics

Facelina species share several defining characteristics:

• Cerata: The most obvious characteristic is the presence of cerata, which are finger-like projections that extend from the back of the animal. These cerata contain nematocysts, which are stinging cells derived from the prey they consume, providing a defense mechanism. The cerata can vary in color and shape between species, offering distinctive identifying features.
• Rhinophores: Facelina species possess rhinophores, which are sensory organs located on the head. They are used to detect food and other stimuli in the environment.
• Size: Facelina species are generally small in size, typically reaching lengths of a few centimeters. They are often brightly colored, with patterns and coloration that can vary significantly between species.
• Diet: Facelina species are carnivores, primarily feeding on hydroids (small, colonial animals). The nematocysts obtained from their hydroid prey are stored in the cerata and used for defense.
• Reproduction: Facelina species are hermaphroditic, meaning they have both male and female reproductive organs. They lay long, ribbon-like egg masses that are often found attached to rocks or other substrates.

Environment

Facelina species are found in a variety of marine environments, including:

• Rocky shores: They are commonly encountered in intertidal zones and subtidal areas with rocky substrates.
• Seagrass beds: Some species inhabit seagrass meadows, where they prey on hydroids growing on the seagrass blades.
• Coral reefs: Facelina species are also found in coral reef habitats, where they may feed on hydroids growing on the coral.

References

• Facelina at World Register of Marine Species
• Nudibranch.com
• Sea Slug Forum - Facelina