An unusual class of bottom marine life appeared about 42 million years ago. Ofiura, or snaketail, are echinoderms. In total, in nature there are a little more than 2,000 different species. In Russia, there are about 120 species, and most prefer to settle in the warm waters of the tropical climate zone. Let's go to the depths of the oceans to get to know these unusual inhabitants of the seas and oceans.
Name
The scientific name Ophiura consists of two Greek words - a snake and a tail. The most diverse type of echinoderms.
Due to the peculiarities of the structure and shape of the body, they are also called snake-tails. While moving along the bottom, their rays develop, resembling small snakes.
By the way, on our site most-beauty.ru there is an interesting article about the most beautiful snakes in the world.
General characteristics
The appearance is reminiscent of starfish. But the ophiura are smaller. The body consists of a disk of various shapes and rays emanating from it. Usually there are 5 rays, but there are species in which the number of rays reaches 10. The skeleton is quite complex. Consists of internal and external parts. The back and abdomen are covered with small scales that protect against external damage.
Microscopic lenses located on the outside of the skeleton form a kind of eye. As such, the organs of vision are absent. The animal simply reacts to changes in light intensity. It is the lenses that help them navigate in space and avoid encountering natural enemies.
In the lower part of the abdomen is the oral cavity, consisting of 5 jaws. They feed on carrion, microorganisms, small invertebrates.
Breeding
They have a very peculiar process of reproduction. In the middle of summer, the mating season begins. Males and females crawl out of shelters onto stones and swab sperm and eggs into the water.
At first males do it. Sperm spreads quickly in the bottom layer of water. A few minutes after spawning, the females crawl out. On four rays they rise on stones, and the fifth ray is lifted above themselves. Pink eggs begin to be thrown into the water, which are fertilized by the liquid of the males.
The female spawns for 4–5 days, each time crawling to the same place, to the same stone.
Significance in nature and human life
Magnificent orderlies of the seabed, as they feed on dead organics, carrion. They themselves are part of the food chain of the oceans.
For humans, fragile sea creatures are not dangerous. And here are their closest relatives, some starfish, poisonous. Fans of marine inhabitants acquire ophiur and keep them in home aquariums along with other animals and fish.
Classification
And now we’ll take a closer look at some of the views of these beautiful and unusual marine inhabitants. Divide them into two large classes. The first is real, whose rays are straight and do not shine. The second is branchy. These have a complex branch-handed structure of the rays.
Оphiarachna incrassata
Predatory ofiarahna olive is widespread in the central Indian Ocean, from the island of Fiji to the east coast of the African continent. It is a predator, but shows its predatory tendencies only during periods of lack of basic food.
Ophiarachna incrassata got its name because of its characteristic greenish-olive color. In diameter, the body reaches a size of 5 cm, but the rays grow to 25 cm. In the process of growing up, the color changes. They live at a depth of 5 to 40 meters.
Easily adapts to life in the aquarium. Because of this, it is quite a popular sight among aquarists.
Ophiothrix fragilis
The five rays of the brittle opiotris are covered with sharp needles. These are the closest relatives of the magnificent starfish. The habitat is limited to the northern part of the Atlantic. Large populations live in the Mediterranean and North Sea.
They have no head and tail, and the body is a disk shell, from which five symmetrical rays depart. The mouth is at the bottom of the disc.
In seawater, the brittle opiotrix moves with its beautiful rays. It feeds on microscopic organisms. Rays are also used for catching prey.
Opiolepis superba
In the scientific literature of the United States and Western European countries, the ophiura opiolepis striped is called a fragile starfish. There is also the name ofiur superba.
The reef invertebrate prefers to hide during the day, and go out at night to search for food. There are gray, light beige with purple stripes. But everyone on the rays of the dark stripes alternate.
They were called fragile stars because of the fragility of the tentacles. This is a kind of protection mechanism. During capture by a predator, the "star" simply casts a ray and is saved.
Ophiomastix annulosa
Ofiura ophiomastix annulosis differs from other rhomboid body shapes. The rays are covered with needles and club-shaped formations.
It lives in the Indian Ocean. Funny creatures prefer the shallow coast of Polynesia, are found off the coast of the Japanese, Maldivian islands and Sri Lanka. It feeds on dead organisms. Rarely, but prey on invertebrate marine life.
The diameter of the unusual shape of the disk reaches 5-7 cm, and the rays grow up to 25 cm. Unpretentious in content, and therefore popular among aquarists. You can buy at pet stores and order online. The price reaches 2,000 rubles.
Ophiocoma sp
The Ophiocom ophiocoma lives along the east coast of North America. Large groups are found in the warm waters of the Caribbean.
The disk has a pentagonal shape. The color is light brown. The rays are slightly lighter than the disk and decorated with dark transverse stripes. Favorite places to stay are coral reefs.
They are found both in shallow water and at a depth of up to 60 meters. In the daytime and in moments of danger, they hide in the crevices of reefs. The main diet is small invertebrates and the dead organic matter of the ocean, which settles on reefs.
Do not miss the fascinating material on our site most-beauty.ru about amazing sea creatures that are absolutely not like ordinary animals.
Ophiomastix janualis
Ofiura Janualis lives in shallow water near the islands of the Indian Ocean. In the north, the range reaches the islands of Japan. Prefers sandy soil.
Striped rays are covered with numerous needles. The diameter of the pentagonal disk reaches 7 cm in diameter. The length of the rays is from 10 to 12 cm. The color is usually dark, almost black.
At home, it gets along well with other aquarium inhabitants. Unpretentious. The main thing is to feed an exotic marine creature in time.
Amphiura stepanovi
In the photo is the Black Sea Wormtail, or, as it is also called ofiura Stepanova. Due to the low salinity of the Black Sea waters, magnificent starfish, hedgehogs and other exotic animals cannot live in them.
But nature has become generous. Amphiura stepanovi adapted to such low-salt conditions and the absence of reefs. They live on a sandy bottom at a depth of 10 to 20 meters. In addition to the sandy bottom, they can live on rocky sediments.
Most species of other ophiur fall into the Black Sea through the Bosphorus. They live in the vicinity of the Bosphorus, as they cannot adapt to the low salt content. Moving on, they die.
Gorgonocephalus arcticus
The specific scientific name gorgonocephalus comes from two Greek words, which literally means "the head of the Gorgon." This is one of the largest in the family ofiur. The gorgonocephalus arcticus disk grows up to 15 cm in diameter.
The length of the branched rays reaches 70 cm. The whole body is covered with a thin skin, and the structure has a symmetrical radial shape. Prefers cool waters, and therefore is widely spread in the waters of the Arctic Ocean, in the northern regions of the Pacific and Atlantic oceans.
They hunt at night, catching small marine life with their long tentacles.
Interesting Facts
We conclude our article on most-beauty.ru with interesting information about the ophiuras who struck the scientific world with their unusual abilities.
- Able to regenerate their rays. But if the animal loses all its rays, the ophiura dies;
- Representatives of the type of gorgonocephalus and other species may glow with a light greenish glow. So they attract small crustaceans, and when touched by a predator, they suddenly “turn on”, scaring off the enemy;
- In the oral cavity there are receptor legs that recognize edible, and inedible discarded;
- At the bottom of the oceans often find prints of fossils ofiur, because these are some of the oldest inhabitants of our beautiful planet;
- In the Black Sea, despite the diversity of marine flora and fauna, there is only one species;
- Depending on the type of food, they send it to the mouth in different ways. Small crustaceans are captured by the tips of the rays, and the remains of fish are rolled into the mouth along the rays;
- Echinoderms, in addition to stars and snaketail, also include holothurians, sea lilies, and hedgehogs. Some types of holothurians are used as food.
Conclusion
Looking at the serpent tail, once again we are convinced how much imagination mother nature has. In ancient Greek myths, gorgons are described. Dangerous creatures with snakes instead of hair. Such a gorgon Medusa was killed by the glorious hero Perseus. Many note that the wriggling snakes on the heads of gorgons resemble the rays of ophiur. Only now the marine inhabitants are pleasing to the eye, and mythical creatures turned people into stone.