holothurian

Under the ocean, there are more than 3,000 species of sea cucumbers and live in seas around the world. They are soft-bodied mollusks, living in all seas around the world, also known by the friendly name sea slugs.

There are many types of sea cucumbers, many colors, bright and beautiful patterns. Although most colorful animals are often poisonous, sea cucumbers are not. Sea cucumbers are also considered the “labourers” of the sea because they eat dead animals, plankton and organic matter on the seabed.

Marbled octopus

The striped octopus (Scientific name: Amphioctopus marginatus ), also known as the coconut octopus, is a species of octopus in the family Octopodidae . They are intelligent species and know how to use coconut shells as mobile shelters. At first they lifted the coconut shell and used their tentacles to sweep away the mud on it. When moving, the tentacles will wrap around half a piece of coconut shell and place it under the body, helping them glide leisurely on the seabed.

Crispy stars

Brittle stars belong to the class Ophiuroidea of the phylum Echinodermata . They are also very colorful creatures and only live in the sea. They are capable of surviving in both shallow and deep seas.

Brittle stars have long arms clearly separated in the central disc region. These arms are long and brittle, breaking easily when injured but also recovering quickly. The brittle star’s digestive system is not yet complete. Although they have a mouth, esophagus, and stomach, they do not have an anus. Therefore, the expulsion of waste takes place through the mouth. These are also scavengers or carnivores.

Mantis shrimp

They have the English name Mantis shrimp because their shape is very similar to a mantis, especially the second pair of thoracic legs shaped like a rudder with large, flexible spines.

The shrimp’s body is only covered by an outer shell from the back of the head to the first 4 segments of the body. Body length can be up to 40 cm, weight 250 g. Body color varies depending on the species from brown, green, light black to pink, light yellow.

Mantis shrimp eat smaller animals, mollusks and crustaceans. They live buried and hidden in caves or rock crevices, only coming out of their shelters to find prey and, depending on the species, can live during the day or at night.

Widely distributed in temperate and tropical seas globally. Delicious meat, can be used as food for people or pets. In Vietnam, 105 species have been discovered, the most common large-sized species is the mantis shrimp Squilla rephidea .

Leafy sea dragon fish

Leafy sea dragon fish has the scientific name: Phycodurus eques, also known as Leafy Sea Dragon, is a species of fish belonging to the Pipefish family. It is the only species in the genus Phycodurus . They are found along the southern and western coasts of Australia. The name comes from its leaf-like shape, used for camouflage.

The leafy sea dragon is the state symbol of South Australia and is the centerpiece of the marine museum.

The leafy sea dragon fish uses its long, small mouth to suck its prey inside. Their favorite food is usually small invertebrates that live around kelp patches in the sea.

Their leaf-like bodies help them camouflage well, making it difficult for aggressive fish to know when to eat them. When they need to defend themselves or attack, they shrink and point out their thorns. This species can stand still for up to 68 hours.

Atlantic flying fish

The Atlantic flying fish has the common English name Flying Gurnard, a species of marine fish in the family Dactylopteridae . This fish lives in warm temperate to tropical waters on both sides of the Atlantic Ocean. Living depth 1 – 100 m.

This fish has variable colors, either brown or green with red or yellow streaks. When excited, they spread their almost transparent “wings,” with bright blue edges. Their wings are used to ward off predators, not to help them move in the ocean like the fins of other flying fish. This type of fish also has large eyes. Their bodies reach a length of up to 50 cm and a weight of up to 1.8 kg.

Christmas tree worms

This species of worm has the scientific name Spirobranchus giganteus , widely distributed throughout the world’s tropical oceans. They are often found “head-first” into large coral reefs on the seabed.

The most noticeable feature of this worm is its two “crowns” that resemble two Christmas trees. These pine trees are responsible for transporting food into the worm’s mouth.

In addition, this is also their respiratory organ, working like gills. Like other worms, Spirobranchus giganteus has a tubular body, surrounded by many hairs and very small limbs that help it move on coral reefs.

However, this worm is very sedentary. Once it has found a favorite location, it will not move much anymore. When attacked, these Christmas trees can also quickly move into the hollows of coral reefs to hide.

Sea cucumber

Sea cucumbers have the scientific name Enypniastes eximia , discovered during NOAA’s Dive 11 in the Gulf of Mexico. This deep-sea sea cucumber is called the “headless chicken monster” by scientists because it has no real brain or sensory organs. However, they still play an important role in filtering sediment on the ocean floor.

The color of Enypniastes eximia varies from bright pink to reddish brown. Notably, their bodies are also transparent, their digestive system can be seen.