Since ancient times, among many peoples, one of the most popular fictional creatures has been a unicorn. Although they described it differently, they always presented it as a horse with a single horn emerging from the forehead. Perhaps for this reason, some representatives of the animal world, which have similar outgrowths on their heads, including fish, became known as unicorns.
The article provides information about unicorn fish: photos, descriptions, habitats and more.
general description
Today, about 16 species of unicorn fish are known, the habitat of which is exclusively the tropical waters of the Indian and Pacific Oceans. These are quite large fish. They reach up to 70 cm in length. They are characterized by laterally flattened and relatively high torso, covered with small and rough to the touch scales. The tail does not have a notch, but it has elongated filiform extreme rays. On both sides of the body, on the lateral surface of the caudal peduncle, there are bone shields that perform a protective function. They are equipped with a pointed thorn or keel.
Adult fish have a grayish or olive color, and young fish are mostly light gray with almost imperceptible tail spines. Unicorns (or rhinos) got their nickname in connection with the presence in older adults of a long horn on their forehead or a pronounced hump. It should be noted that in males it is more massive than in females, and young fish on their forehead have only a small pointed protrusion.
Adult individuals mainly live in coastal wave sections of the outer slopes of rocky shores and coral reefs. You can meet them in large shoals, flocks and one by one.
Local residents eat the meat of this fish for food, despite the fact that it has a bitter taste and even often causes poisoning.
Lifestyle, reproduction
These fish are mostly secretive daytime, eating quite actively. Their diet includes attached brown algae. Together with them they eat bottom small invertebrates. Some species include corals, hydroids, and even sponges.
Unicorn fish spawning occurs on the full moon in December-July. During the breeding season they keep in packs, from which small spawning groups are separated from time to time, sharply rushing up. Females spawn in the surface waters of the ocean. They have a small pelagic one, and their development after fertilization in the tropics continues for about a day.
Larvae emerging from eggs after 5 days begin to actively feed on planktonic organisms. Initially, they have no external similarities with their parents, so for a long time they were assigned to independent species. After 2-3 months, the larval stage is completed, and young fish begin to approach the shores, where they are transformed within 5 days. They become like adult fish.
During this period, there is a change in color, and lengthening of the digestive tract (about 3 times) in connection with a change in diet (less calorie algae). In the coastal part of the ocean, juveniles quickly grow stronger and grow, gradually moving to deeper reef zones. It is characteristic that the fry of unicorn fish have a normal-shaped head. A typical horn on their forehead appears only with a head length of more than 12 cm.
Unicorn comb fish
Information about unicorns would be incomplete without mentioning the poorly studied and rarely found representative of the ichthyofauna of deep waters. Its English name is literally translated as a unicorn comb-fish. Only 3 species of these unique fish live in the tropical zone of the oceans. They are found everywhere at depths of more than 1, 000 meters.
These marine animals are characterized by a thin elongated silvery body (150 cm - the size of adults) and the presence of a long red dorsal fin extending from the head to the tip of the tail.
The comb fish got its name for a solid horn-shaped outgrowth located on the head. It is located on the upper jaw and protrudes far forward. Scientists believe that the main attraction of this fish is an ink bag, which allows it, in case of danger, to throw out a cloud of ink from the cloaca and leave it under its cover. Although the same scientists believe that a black cloud cannot help to escape in such darkness from an attacking predator, which, most likely, finds its prey by smell or by fluctuations in water.
Whale narwhal
Unicorn whale fish is included in the Red Book and is an inhabitant of the Arctic seas. This is the rarest whale in the world, and the most mysterious animal of the ocean.
It has a large horn (or tusk), making it special and unique. The male’s tooth turns with age into a tusk twisted by a spiral. Its length is about three meters, weight reaches up to 10 kg.
An interesting fact is that the remaining teeth of these whales do not turn into tusks.
