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Blue Sea Slug » Main characteristics and Way of Life

In this article we talk about the Glaucus Atlanticus, a rare mollusk commonly known as the Blue Dragon and also as Sea Slugs.

It is a species of gastropod mollusk, a unique marine animal belonging to the family Glaucidae.

Main characteristics of Blue Sea Slug

One of the most outstanding characteristics of this rare mollusc is its dimensions. The size of the Glaucus Atlanticus varies between 3 and 4 cm long, rarely reaching 5 cm. It is so small that it fits perfectly in the palm of a human being’s hand.

It is also characterized by a gas pocket in its stomach. This bag helps it to float upside down, preventing it from leaving the surface of the water. By the way, this rare animal spends most of its life moving around on the bottom of the sea.

The Glaucus Atlanticus is one of the most colourful sea slugs.

It has a very striking and unusual colour, between blue and silver. Also, some blue and black stripes along the foot.

On its back it has two lines of more intense blue that go from the length of its body to the tip of its tail. It has teeth that look very much like swords.

Researchers describe its body as a flattened trunk with six appendages that are divided into rays. Glaucus Atlanticus has no shell for the simple reason that it doesn’t need one.

When it is floating, the silver-colored underside of its body serves as a defense mechanism by using it as a camouflage, so predators will not be able to identify it.

It is not good to rely only on the tiny and harmless appearance, this rare animal hides a hidden weapon: it is very toxic.

Glaucus Atlanticus is able to digest the most lethal poison of marine species, make a combination and then use it to defend itself.

Natural habitat of Glaucus Atlanticus

The Blue Sea Slug is pelagic, that is, it can be found in most oceans and sea waters, in both temperate and tropical areas of the planet.

Some regions where it is found include the east and south coast of South Africa, European waters, the east coast of Australia and Mozzambique.

Often accidentally and out of reach of this animal, the wind pushes them towards the beaches where they become stranded. This can cause them to expand in those areas.

What do these exotic and rare molluscs eat?

The main food source for this rare animal is other living creatures found in the sea such as jellyfish, corals and sea anemones.

One of the main components of its diet is the Portuguese jellyfish which is highly poisonous and much larger.

However, it devours it in its entirety, then selects these poisonous toxins from which it has become immune and takes them to its stomach where it stores them for its own use, thus transforming the poison into a more deadly one.

The poison is stored by means of specialized sacks on her fingertips which are located on her extremities.

This poison becomes more powerful than the one possessed by the animal that ingested it and that it will use later to defend itself when it is in danger.

In the extreme case that it does not get its favorite food, that it is very hungry or that there is an animal of the same species in its area, the Blue Sea Slug becomes a carnivore. In other words, it is a predator in every sense of the word that will do everything possible to survive.

How Glaucus Atlanticus reproduces?

Glaucus Atlanticus is a rare mollusc that has both male and female reproductive organs, i.e. it is hermaphroditic.

Mating is believed to take place through the ventral part and not the right.

After they reproduce they create chains of eggs, which are then attached to other elements found in their habitat such as pieces of wood, garbage and even the remains of dead animals.

Because this species is hermaphrodite it is not in danger of extinction, really its way of reproducing is impressive.

What are its predators?

According to research, this type of species does not have many predators, but its survival is determined by weather conditions and water temperature.