6 créatures qui vivent dans les fonds marins

6 creatures that live on the seabed

Scientists know more about space than they do the ocean , according to Columbia University 's Earth Institute. So, in a sense, the majority of creatures lurking beneath the surface might as well be aliens.

On the other hand, researchers at Dalhousie University, in Nova Scotia (Canada), estimate that 91% of these marine animals are still unknown to us. Among the approximately 235,000 species we know of, many have adapted to their environments through distinctive camouflage , bioluminescence and mating habits, resulting in some very strange appearances.



Scientific experts have given this fish a name, which is “ Psychrolutes microporos ”, but it is also known by the more common and straightforward name “ Fathead ”. This is a species of fish that is often recognized for its large head and unique body shape.

Smithsonian Magazine even notes that this bizarre-looking creature is widely considered "the ugliest animal in the world." But the blobfish is a pretty incredible sea dweller, surviving at depths of over 4,000 feet , where the pressure is 120 times that at the surface. And here's the thing: the blobfish is only really ugly when it's brought to the surface. Most fish have a swim bladder , which is a bag of air inside their body that allows them to float.

When fish are removed from their usual environment, these sacs inflate and the innards come out through the mouth. Technically, we only consider the blobfish ugly when it's dead - so think twice before pointing at it and laughing.

Features Values
Scientific name Psychrolutes marcidus
Lifetime About 130 years old
Size Between 30 and 90 cm
Weight Between 2 and 10 kg
Physical appearance Flabby body, no swim bladder, gelatinous and wrinkled skin, small and black eyes, wide and smiling mouth


One of the most interesting creatures of the seabed is the Tardig rade , more commonly known as the moss pig or water bear . There are many different species of tardigrades, several of which are found on the sea floor.

The largest Tardigrade species are 1 ½ millimeters long , barely visible to the naked eye. Surprisingly, Tardigrades do not fear freezing or boiling water temperatures. They may also go without water or food for years. They may shrivel up completely, but can rehydrate and continue to live.

Features Values
Scientific name Tardigrada
Lifetime About 1 year
Size Between 0.1 and 1.5 mm
Weight A few micrograms
Physical appearance Cylindrical body, four pairs of clawed legs, head with a stylus, protective cuticle, often translucent or pigmented

Giant worm

The giant worm is another fascinating seabed creature . It is a large , flattened worm that can reach 1.5 m in length. These blue or purple worms have many segments, each with its own pair of legs, much like the ground centipede. The giant worm burrows into the sand of the seabed, where it searches for small objects to eat.

Features Values
Scientific name Megascolides australis
Lifetime Unknown (maybe more than 5 years old)
Size Up to 8 meters long
Weight Can reach up to 1 kg
Physical appearance Cylindrical body, smooth and shiny skin, pointed head, several visible rings around the body, pale pink color

Giant clam

Many types of bivalves are found on the seabed. Perhaps the most famous bivalve is the giant clam . These sea creatures have two massive, wrinkled shells that open and close with a powerful internal muscle.

Giant clams are impressive not only because they can weigh more than 200 kg or live 100 years, but also because they are often beautifully colored . Giant clams anchor themselves to the sea floor or to coral growing on the ground, then open their shells to collect passing food.

Features Values
Scientific name Panopea generosa
Lifetime About 100 years old
Size Up to 1.2 meters long
Weight Can reach up to 220 kg
Physical appearance Thick, stocky, elongated shell, dark gray-brown to black color, pearly white interior, soft, fleshy body, cream to beige color

The pleated ascidian

Sea squirts , or tunicates , are another type of visually stunning sea creature. These invertebrates attach themselves to the sea floor and filter the water to recover nutrients.

There are hundreds of species of ascidians, found all over the world. They are usually tubular in shape and come in many bright colors , including white , orange , red , green , purple and blue .

Features Values
Scientific name Ciona intestinalis
Lifetime About 2 years
Size Up to 15 cm long
Weight About 30g
Physical appearance Bag-shaped body, transversally pleated, variable color (from white to dark brown), two siphons: one for water entry and one for waste outlet


Cumaceae are tiny crustaceans , called hooded shrimps because of their long, thin tails and rounded bodies. Many Cumacean species burrow into the seabed where they hunt for food. They are found all over the world, in a variety of water temperatures and habitats . They are only a centimeter or less long.

Features Values
Scientific name Cumacea
Lifetime About 1 to 2 years
Size Between 2 and 20 mm
Weight Varies depending on the species
Physical appearance

Oval and laterally compressed body, hard and often pigmented carapace, several pairs of biramous legs, two antennae and two compound eyes

In conclusion, the seabed is full of fascinating and often little-known creatures. The six creatures presented in this text are all examples of the incredible diversity and adaptation of underwater life.

These extraordinary animals remind us that the oceans are a complex and fragile ecosystem, the preservation of which is essential for the future of our planet. We still have much to learn from these mysterious creatures , and it is important to continue to explore and study the ocean floor to better understand how they work and why they are important.

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