Brown-line Paperbubble

• The mantle, deep pink with a bluish-white margin, wraps almost the whole shell when the animal is active.
• Its shell is extremely thin and translucent, with brown spiral bands, and it is almost covered by a pink, ruffled mantle with a shining edge, which gives it an appearance very unlike a snail's.
• It is a specialised predator: it eats polychaete worms, above all from the cirratulid group, which it locates beneath the sand and swallows whole.
• Its body is too big to fit in the shell, so it cannot retract: it depends on burying itself to escape.
• It is a hermaphrodite, and its egg masses are coiled gelatinous strings that it fixes to the sand.
• Like the striate bubble, it illustrates the evolutionary transition towards the loss of the shell in the opisthobranchs.

Skeleton type

Invertebrate - external calcareous shell (mollusc)

Habitat and environment

Shallow sandy bottoms of tropical Indo-Pacific reefs

Sources consulted: Rudman, Sea Slug Forum; Malaquias, revisiones de Aplustridae; Museo Australiano