Scientific Name: Volvatella angeliniana

Adult Size: 10 – 25 mm
Depth Range: 1 – 15 m; most common in sheltered lagoons and seagrass beds
Biotope / Habitat: Found on or near its host algae, especially Caulerpa species, where it feeds and hides among fronds
Diet: Specialist herbivore feeding on green algae (Caulerpa spp.); uses its radula to pierce algal cells and suck out their contents
Reproduction: Simultaneous hermaphrodite; lays gelatinous, ribbon-like egg masses attached to algae. Eggs develop into free-swimming planktonic larvae before settling on suitable algae.
Fun Fact: With its delicate, semi-transparent shell and smooth, bubble-like body, Volvatella angeliniana looks more like a tiny glass ornament than a sea slug. Its translucent mantle often shows the green tint of the algae it feeds on, helping it blend perfectly with its surroundings.

Graceful and fragile-looking, Volvatella angeliniana is a sacoglossan sea slug that carries a thin external shell—a rare trait in the sea slug world. For divers and photographers, spotting this tiny, algae-hugging jewel is a special reward during a slow, observant macro dive.