Scientific Name: Favorinus mirabilis
Common Name: Favorinus nudibranch
Size: Up to 15 mm
Depth Range: 3 – 30 m

Identification:
Favorinus mirabilis is a small, elegant aeolid nudibranch recognized for its slender, translucent body, which often displays hints of pink or cream. Its standout features are its numerous slender cerata, each tipped with vivid orange or reddish coloration that contrasts beautifully with its pale body. The head bears long, smooth rhinophores and oral tentacles that are usually semi-transparent. The overall delicate appearance of this nudibranch makes it a favorite among macro photographers.
Habitat:
Usually found on coral rubble, dead coral, or algal-covered rocks in sheltered reef areas. It often inhabits places where other opisthobranch egg ribbons are present, as these serve as its food source.
Diet:
Specializes in feeding on the eggs of other sea slugs (opisthobranchs), using its radula to rasp and consume the egg masses.
Reproduction:
A simultaneous hermaphrodite like most nudibranchs. After mating, it lays its own delicate, coiled egg ribbons, often on hard substrates. The larvae are planktonic before settling onto the reef.
Fun Fact:
Favorinus mirabilis plays an interesting ecological role as a predator of other sea slug eggs, which may help regulate opisthobranch populations in reef ecosystems.

Observation Tip:
Look closely at sea slug egg ribbons — you may spot this tiny nudibranch feeding! Its small size and translucent body make it easy to overlook without a careful eye.