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 small, blue sea slug, a pelagic aeolid nudibranch, a shell-less gastropodmollusk in the familyGlaucidae.[2]
These sea slugs are pelagic; they float upside down by using the surface tension of the water to stay up, where they are carried along by the winds and ocean currents. Glaucus atlanticus makes use of countershading: the blue side of their body faces upwards, blending in with the blue of the water. The silver/grey side of the sea slugs faces downwards, blending in with the sunlight reflecting on the ocean’s surface when viewed facing upwards underwater.
Glaucus atlanticus feed on other pelagic creatures, including the Portuguese man o’ war and other venomoussiphonophores. This sea slug stores stinging nematocysts from the siphonophores within its own tissues as defence against predators. Humans handling the slug may receive a very painful and potentially dangerous sting
Thank you for sharing @Garnet! Well aren’t they adorable just tumbling around there! Now whenever I am out in the oceans I will be looking for them.
I won’t mind if they take care of the Portuguese Man O War that we have around here though. My daughter got stung by one at the beach down the street from us. It wrapped around her legs as she went by then she was out of the water for a couple days. Much to her dismay. She was uncomfortable & we did what we could for her, she just needed some coaxing back into the water. We told her that she shouldn’t be mad at it because it probably wasn’t intentional & she thinks we are crazy now.