Sea Worm: Species, Description and Features of Breathing

Sea worms are unusual creatures. Many of them are like fantastic flowers or bright flat ribbons, but there are species that evoke a shiver of horror with their appearance and habits. In general, the sea worm is a very interesting creature. It can be a spiny-headed, multi-bristled, ring-shaped species, flat, hairy and so on. The list is really huge. In this article we will get acquainted with several species in more detail.

Sea worm tubular, polychaete

A sea worm, whose photo looks like an exotic flower, is called a tubular polychaete or "Christmas tree". This vivid species belongs to the Sabellidae family. The Latin name of the animal is Spirobranchus giganteus, and the English name is Christmas tree worm.

This species of marine worm lives in the zone of the tropics of the Indian and Pacific Ocean. Prefers small depths, coral thickets and clear water.

To feel protected, this sea worm builds a calcareous tube of calcium and carbonate ions. The animal extracts its building material directly from the water. For the bond of ions, the "New Year tree" allocates a special organic component from the two mouth glands. As the worm grows, the tube has to be added, attaching new rings to the end of the old shelter.

Larvae of the polychaete tubular worm to choose a place under the house are responsible. They start building only on dead or weak corals. Sometimes they gather in whole colonies, but solitary houses are often found. Growing up, corals hide the tube, leaving on the surface only a smart multi-colored "Christmas tree". By the way, the color of the sea worm is really bright and saturated. It can be blue, yellow, red, white, pink, mottled and even black. There are a lot of options. Several individuals combine different colors.

A beautiful outdoor "Christmas tree" is not just an ornament, but gill rays that perform the work of the bodies of nutrition and respiration. Each sea worm has two spiral gill rails.

About their security, polychaete ringworms are taken care of at the stage of building a house. Lime tube has a dense lid, at the slightest threat the worm pulls inward and slams the entrance.

Depending on the type of Spirobranchus giganteus live from 4 to 8 years.

Polychaetes

Polychaetes belong to the type of annelids, the class of Polychaetes. In nature, they live more than 10 thousand species. Most live in the seas and lead a bottom way of life. Individual families (for example, Tomopteridae) live in the perialial (open sea or ocean, not touching the bottom). Several genera live in fresh waters, for example, in Lake Baikal.

Sea dumper

One of the most common representatives of polychaetes is the ringed polychaete sea worm, whose name is the sea dun. In Latin it sounds like Arenicola marina. The animal is quite large, its length reaches 20 cm. This sea worm lives in arched mink, dug in the bottom sand. Nutrition for this species is a bottom sediment, which the worm passes through the intestine.

The body of an adult specimen consists of three divisions - thorax, abdomen and caudal. The outer cover forms secondary rings that do not correspond to segmentation. The abdominal segments in the body of the worm are 11, and in each one there are paired bushy gills.

The sea dunnage strengthens the walls of its home with mucus. The length of the mink is about 30 cm. While in the house, the worm has the front end of the body in the horizontal section of the mink, and the back is in the vertical section. Above the head of the worm on the ground, a funnel is formed, as it constantly swallows bottom sediments. For defecation, the sand dune exposes the rear end from the mink. At this point, the sea-worm can become a prey of a predator.

Nereid

Nereid is a marine ringworm. It is a creeping species that serves as food for many marine fish. The body of the worm consists of segments. At the anterior point is the head, on which tentacles, mouth, jaws and two pairs of eyes. The sides of the segments are provided with flat processes similar to the blades. Numerous long setae are concentrated here.

In the Nereid, the whole surface of the body is involved in breathing. So do the ringed earthworms that are familiar to everyone. The nereid moves, rapidly moving with lobate-like outgrowths. At the same time, the body is supported by tufts of setae on the bottom. In its menu, this marine ringworm includes algae and small animals, which have jaws.

Features of breathing

The method of breathing, which uses Nereids, can be considered for this type of worm exception to the rules. How do the other representatives of the ringed breathe? What is common in the breathing of marine annelids? The breath of most species occurs through the gills, which are located on the outgrowths-lobes. Gills are equipped with a large number of capillaries. Enrichment of blood with oxygen comes from air, which is dissolved in water. Here, carbon dioxide is released into the water.

Marine flatworms

In the ocean depths there is another class of worms - marine flatworms. They are called ciliary or turbellarians. To this class are more than 3,5 thousand species. The body of representatives is covered with ciliated epithelium, which helps to move. Some representatives of ciliated worms can be considered only under a microscope, but there are species reaching 40 cm in length. Among the flatworms are not only free-living marine species, but also parasitic, including banded.

A sea flat worm is more often a predator. Moves it crawling or swimming. It is a bilaterally symmetrical animal. The turbellarians have a flattened body of oval or elongated shape. On the front of the body are the sensory organs, and the mouth on the ventral side.

The digestive tract of ciliated worms depends on the species. It can be quite primitive or rather complex, with a branched intestine.

Some species of marine turbellarians are not strikingly inconspicuous, but there are brightly colored and handsome people who can not be missed.