The inverted swimming slug-The Blue Dragon

A small-sized species of blue sea slug is the legendary Blue Glaucus, or Glaucus atlanticus as it is called by its scientific name. Its recognizable, brilliant blue tones have attracted a lot of attention in past years. Additionally, a number of names have been coined for these colors, including a blue dragon, sea swallow, and blue angel.

Blue Glaucus

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The species is a pro at disguising itself. The Blue Glaucus, though it occasionally washes up on beaches and startles swimmers, uses its vivid colors to blend in with the water and sky. It is renowned for devouring venomous creatures and scavenging their poisons, and it also has a reputation for being both angelic and lethal. The Blue Glaucus has a life span of one month to one year.


The body of the Blue Glaucus has a coloring pattern called countershading. Its head is striped with dark blue lines, and its lateral side is silvery grey. Its ventral side is dark and pale blue. As it floats on the ocean's surface, this color offers it vital defense against predators both above and beneath it. The dark blue hue may also serve to deflect dangerous UV radiation.

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The Blue Glaucus also has a flattened, tapering body and six appendages that branch out into cerata that resemble fingers—eighty-four in all. When feeding or when the Blue Glaucus feels threatened, cerata, which are long, thin structures, are deployed to sting. It also features radular teeth that mimic the serrated edge of a blade.


They are hermaphrodites, which means they can create both sperm and eggs, which is an interesting characteristic of this sea slug. However, they still need to mate with another slug in order to lay viable eggs. The Blue Glaucus merely floats around until they discover a partner, which is similar to how they hunt.

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Fish that reside farther from the coast or the bottom of the ocean, such as blue glaucus, are called pelagic. They live in the seas of the Atlantic, Pacific, and Indian Oceans and may be found all over the world. The Blue Caucus loves to float backward on the ocean's surface tension. To stay buoyant, they ingest air bubbles and store them in their gas-filled sac before letting the wind and ocean currents transport them. They occasionally drift to the sand at the ocean's bottom.


While the blue dragon has many interesting characteristics, its diet is possibly the most intriguing. It prefers to eat the dreaded and poisonous Portuguese man of war cnidarian.

Portuguese man of war

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Although the Portuguese man of war (Physalia physalis), which is sometimes mistaken for a jellyfish, is actually a type of siphonophore, a family of creatures related to jellyfish, a siphonophore is unique in that it is made up of a diverse array, genetically identical individuals known as zooids, or clones, that have different shapes and functions yet collaborate as a single unit. A man of war's four specialized components, which include those for floating, catching prey, eating, and reproduction, are each in charge of carrying out a certain duty. 

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In addition to eating it, the Blue Glaucus reuses the Portuguese man of war's stinging cells for use in their defense mechanisms. The blue dragon may accumulate a sizable number of these stinging cells, which are shielded from them by hard discs inside its skin and a coating of protective mucus. Since this species engages in cannibalism often, the majority of this sea slug's predators are other Blue Glaucus.


A further danger to the Blue Glaucus is climate change. They are negatively impacted more particularly by ocean acidification, which is brought on by a rise in CO2 in the atmosphere. Because fewer Portuguese men o' War are eating as much food, ocean acidification eventually has a negative impact on Blue Glaucus populations.


Until next time, stay happy and stay safe.

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