Leopard Sea Slug

Mollusc

Identification & Biology

• IdentificationA large, oval dorid nudibranch with a soft, leathery mantle covered in a dense pattern of dark brown or black spots on a pale cream to yellow background. A ring of retractable gills at the rear and two club-shaped rhinophores at the front.
• SizeBody length up to 12 cm. One of the larger nudibranchs in the Mediterranean.
• Social HabitSolitary. Slow-moving. Almost always found on or near the Petrosia ficiformis sponge on which it feeds.
• HabitatRocky reefs and walls with large sponges. Strongly associated with its prey sponge.
• Depth5 to 50 m. Most common between 10 and 40 m.
• Feeds OnAlmost exclusively the sponge Petrosia ficiformis. Feeds by rasping tissue from the sponge surface.
• DistributionMediterranean Sea and adjacent eastern Atlantic. Common in Maltese waters wherever its sponge prey is found.
• DescriptionPeltodoris atromaculata is frequently found sitting on the dark, stony sponge Petrosia ficiformis, its spotted pattern surprisingly effective as camouflage against the sponge surface. The two species are so closely associated that finding the sponge is often the fastest way to find the nudibranch. It is one of the most commonly encountered and photographed nudibranchs in Malta.