Margined Sea Lizard

Glaucus marginatus

Vaguely resembling a tiny lizard this creature is actually a glittering blue nudibranch mollusc. It reaches only 10 mm in length and has 3 pairs of fan-like finger-like appendages called cerata. Sea Lizards float upside-down on the water surface and can somersault and ‘row’ using their cerata that also act as gills. They feed on Blue Bottles and By-the-wind Sailors and store stinging cells from these animals in the terminal sacs of their cerata. These stinging cells are used for the creature’s defence and can occasionally cause minor stings to swimmers.

Sea Lizards are found throughout the Pacific and Atlantic Oceans.

Margined Sea Lizard (Glaucus marginatus) Margined Sea Lizard (Glaucus marginatus)

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