Glaucus atlanticus

Species of mollusc

Glaucus atlanticus (common names include the blue sea dragon, sea swallow, blue angel, blue glaucus, dragon slug, blue dragon, blue sea slug, and blue ocean slug) is a species of sea slug in the family Glaucidae. These sea slugs live in the pelagic zone (open ocean), where they float upside-down by using the surface tension of the water to stay afloat. In addition, they have a gas bubble in their stomach that makes it easier for them to float.

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