Dotted Sea Slug

The dotted sea slug, also called the sea cow, is a chunky white nudibranch, a sea slug with no shell. Dark brown spots splash across its body, making every individual look slightly different.

Also known as: sea cow, leopard-spotted sea slug, Discodoris atromaculata, vaca suiza, vaquita suiza, Peltodoris atromaculata

This species is sometimes grouped in with the related genus Discodoris. But its brown spots crowd more thickly toward the middle of the back and thin out near the edges, instead of spreading evenly.

Its mantle, the soft outer body covering, is white and scattered with brown spots in no set pattern. Each spot has a darker brown ring around it. The amount of spotting differs between animals, but it never covers more than half the mantle. It grows up to 7 cm.

This slug feeds only on two sponge species, Petrosia ficiformis and Haliclona fulva. It finds them by sensing chemicals in the water. It likes Haliclona best but eats mostly Petrosia, simply because there is more of it around. Both sponges are toxic to almost everything else, so the dotted sea slug has little competition for its food.

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  Black-margined Nudibranch

  Doriprismatica atromarginata

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  Blue dragon

  Glaucus atlanticus

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  Cratena Slug

  Cratena peregrina

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  Faithful Sea Slug

  Goniobranchus fidelis

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  Four-lined Polycera

  Polycera quadrilineata

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  Fried egg nudibranch

  Phyllidia varicosa