Blue Sea Slug - Two Glaucus atlanticus and a Glaucus marginatus (or Glaucillus marginatus)

These small sea slugs float on the sea and are blown onto shore during the summer months onto Central Coast beaches. These were collected at MacMasters Beach in New South Wales. The Blue Sea Slug feeds almost exclusively on the tentacles of the stinging bluebottles. The larger ones are Glaucus atlanticus, with a single row of pinnae, while the smaller one has multiple rows of pinnae, hence is Glaucus marginatus. See more information on my website: One of the best sites for further information is the Sea Slug Forum run by Bill Rudman it is excellent The British Museum of Natural History has also good information about Glaucus atlanticus
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