Common name: Flat camouflaged slug

General information

Plakobranchus ocellatus, commonly known as the Sapsucking Slug or Eastern Emerald Elysia, is a species of sacoglossan sea slug, a marine gastropod mollusk. This species is notable for its vibrant green coloration, which is a result of the chloroplasts it retains from the algae it consumes. This process, known as kleptoplasty, allows the slug to utilize photosynthesis, supplementing its diet with energy from sunlight.

Care

In the aquarium, Plakobranchus ocellatus requires a specialized setup that includes a source of the specific algae it feeds on. The tank should have ample live rock and a mature algae growth to sustain them. They are sensitive to water quality and require stable conditions with excellent water filtration.

Reproduction

Reproduction in Plakobranchus ocellatus involves laying clusters of eggs on the substrate or on algae. The larvae that hatch are planktonic and will require microscopic algae or phytoplankton to survive. Breeding them in captivity is challenging due to the difficulty in providing appropriate food for the larvae.

Symbiosis

The most fascinating aspect of Plakobranchus ocellatus is its ability to incorporate chloroplasts from the algae it eats into its own tissues, a symbiotic relationship known as kleptoplasty. This allows the slug to survive for months by photosynthesizing, which is highly unusual for an animal.

Habitat

Plakobranchus ocellatus is found in warm, shallow waters where its food source, algae, is abundant. They are often seen in the Indo-Pacific region, grazing on algae on coral reefs and rocky substrates.