Blind sea spiders. The sea spider is a mysterious inhabitant of the depths. "Starfish and Spider"

Squad - perciformes Family - sea dragons Maximum length - 40 cm Fishing places - shallow water with a sandy bottom Fishing method - small path The sea scorpion (Trachinus araneu; in Italian - sea spider) has a more “squat” body shape than its relatives, a massive head , the mouth is large, almost vertically cut, relatively small eyes, in front of which there are two pointed outgrowths. On the back rises the first dorsal fin of seven spiny rays with poison-producing glands, the second, longer, support soft rays. The anal fin is very long, the ventrals are medium in size, the tail is in the form of a spade. On the gill covers are spikes with poison-producing glands. The color of the body is brown or yellow-brown, the upper part is covered with a variety of round and oval spots, forming longitudinal stripes on the sides.

Reproduction and size of the sea scorpion, spider

Spawning in the sea scorpion occurs in the spring and summer months, the maximum length of adults reaches 40 cm.

Lifestyle and nutrition of the sea spider, scorpion

The sea scorpion lives in shallow water on a sandy bottom, where it burrows and, merging with environment waiting for prey. This predatory fish feeds on crustaceans, molluscs and fish larger than itself. Usually, the sea scorpion, having attacked the prey, plunges its thorns into it *, lets poison into the prey, which paralyzes it, and it quickly dies. This fish is also very dangerous for humans, as the sting of its thorns can cause very painful allergic reactions. * The sea scorpion uses its thorns exclusively for self-defense

How to catch sea scorpion, spider

Track. Sea scorpion is most conveniently caught in coastal waters on a small bottom path using natural baits. In gear, a sinker is used, mounted on a fishing line and attached with a block to a leash 5 m long. Having lowered the nozzle to the bottom, they try to lure the sea scorpion out of its shelter. In order to fish on the track, you need to be a mile and a half away from the coast, and with artificial baits you can sail more than three miles. A sea scorpion caught on a hook reacts quite quickly, but it is usually not difficult to pull it out. When the fish is already in the boat, remove the hook very carefully, trying not to get hurt by its dangerous spikes. You can catch sea scorpions all year round but the best time to do this is in the spring. The most favorable hours for such fishing begin at dawn and end at noon. Nozzles. The sea scorpion cannot resist all sorts of sea ​​worms, whole sardines or pieces of it, crustaceans, tentacles and strips of squid or cuttlefish. The most catchy spinners are curved spoons, especially shiny, 2-3 cm long.

The systematic and evolutionary position of which has not yet been fully determined. Despite the name, sea spiders (Pycnogonida) have nothing to do with real spiders, although they are considered as an early isolated group of the chelicerate subtype, which includes arachnids and merostomes, that is, horseshoe crabs and crustaceans.

sea ​​spiders- this is a relatively small group, currently numbering about 1300 species. The earliest finding of a sea spider in the form of a larva dates back to the Cambrian period, there are also descriptions of finds from the Silurian and Devonian deposits.

These are very strange, morphologically unlike animals, consisting almost entirely of legs alone. Their body is so tiny that it does not even fit half of the internal organs that normal animals should have there. Therefore, for example, sexual and digestive system sea ​​spiders are found entirely in the legs. And their legs, although luxurious, are rather frail due to weak muscles, so sea spiders are very unhurried creatures and can spend 40 minutes without any movement at all. Because of this, bryozoans and all sorts of polyps grow on them, and amphipods and sea goats are happy to use these stilts as a substrate. Particularly leisurely individuals even manage to fall into a trap - they do not move for so long that a sponge has time to grow around their legs. But long legs allow you to move on any, even the softest substrate, and sea spiders can be found almost everywhere, from the tidal zone to deep-sea habitats.

The life of a sea spider is the life of a leisurely benthic vagrant. Any mobile prey is faster than this predator, and therefore it mainly feeds on attached soft organisms like hydroid polyps. At the front end of the spider's body there is a tiny head with a rigid trunk and heliphors armed with claws. The spider uses a trunk to suck out polyps, and with claws it tears off soft pieces from the victim, which are then digested in the processes of the midgut located in the legs (!). I must say that real spiders also have intestines with lateral processes, but they are much shorter and do not go into the limbs. By the way, it is interesting that sea spiders do not have any gas exchange organs - it is believed that with such a leisurely lifestyle, the tiny amount of oxygen that is absorbed through the surface of the body is enough.

On the tiny head of a sea spider is a small eye tubercle with two pairs of eyes that distinguish between light and shadow and, possibly, the contours of objects. With the help of these eyes, the male spider finds the female, whose slender legs are filled with maturing eggs, sits on top of her and rides on her, waiting for the eggs to mature. Most sea spiders have separate sexes, but one hermaphroditic species is also known - Ascorhynchus corderoi.

Unlike other arthropods, sea spiders have several pairs of genital openings, and they are located on walking legs. After the eggs have matured, the female lays them, and the male immediately fertilizes the clutch. Then the male collects eggs in cocoons, fastening them with a gelatinous substance, which is secreted by cement glands, also located on his legs, and puts them on special egg-bearing legs. Mating of sea spiders lasts from half an hour to several hours, and in some species it can last for weeks. After the end of this unhurried process, the care of the offspring falls entirely on the shoulders of the male, and in the literal sense: he wears cocoons on himself until the very late stages of embryonic maturation. Moreover, during the season, the male can mate with several females, and then there will be several cocoons from different mothers on his egg-bearing legs.

See also:
Sea spiders, "Nature", No. 8, 2006.

Veronika Samotskaya

(the average: 4,62 out of 5)

Yesterday, September 26, was World Maritime Day. In this regard, we bring to your attention a selection of the most unusual sea creatures.

World Maritime Day has been celebrated since 1978 on one of the days last week September. This international holiday was created in order to draw public attention to the problems of pollution of the seas and the disappearance of animal species living in them. Indeed, over the past 100 years, according to the UN, some species of fish, including cod and tuna, have been caught by 90%, and every year about 21 million barrels of oil enter the seas and oceans.

All this causes irreparable damage to the seas and oceans and can lead to the death of their inhabitants. These include those that we will discuss in our selection.

This animal got its name due to the ear-like formations protruding from the top of its head, which resemble the ears of the Disney elephant Dumbo. However, the scientific name of this animal is Grimpoteuthis. These cute creatures live at depths of 3,000 to 4,000 meters and are among the rarest octopuses.

The largest individuals of this genus were 1.8 meters long and weighed about 6 kg. Most of the time, these octopuses swim above the seabed in search of food - polychaete worms and various crustaceans. By the way, unlike other octopuses, these swallow their prey whole.

This fish attracts attention, first of all, with its unusual appearance, namely, bright red lips on the front of the body. As previously thought, they are necessary to attract marine life that the bat feeds on. However, it was soon found out that this function is performed by a small formation on the head of the fish, called an eska. It emits a specific smell that attracts worms, crustaceans and small fish.

The unusual "image" of the bat complements at least amazing way his movement in the water. Being a poor swimmer, he walks along the bottom on his pectoral fins.

Short-nosed bat - deep sea fish, and lives in waters near .

These deep sea animals have many branched rays. Moreover, each of the rays can be 4-5 times larger than the body of these brittle stars. With the help of them, the animal catches zooplankton and other food. Like other echinoderms, branched brittle stars have no blood, and gas exchange is carried out using a special water-vascular system.

Usually branched brittle stars weigh about 5 kg, their rays can reach 70 cm in length (in branched brittle stars Gorgonocephalus stimpsoni), and the body is 14 cm in diameter.

This is one of the least studied species that can, if necessary, merge with the bottom or imitate a twig of algae.

It is near the thickets of the underwater forest at a depth of 2 to 12 meters that these creatures try to stay so that in a dangerous situation they can acquire the color of the ground or the nearest plant. In the “calm” time for harlequins, they slowly swim upside down in search of food.

Looking at the photograph of the harlequin pipe-nosed, it is easy to guess that they are related to seahorses and needles. However, they differ markedly in appearance: for example, the harlequin has longer fins. By the way, this form of fins helps the ghost fish to bear offspring. With the help of elongated pelvic fins, covered on the inside with filamentous outgrowths, the female harlequin forms a special bag in which she bears eggs.

In 2005, an expedition exploring the Pacific Ocean discovered extremely unusual crabs that were covered with "fur" at a depth of 2,400 meters. Because of this feature (as well as coloration), they were called "yeti crabs" (Kiwa hirsuta).

However, it was not fur in the truest sense of the word, but long feathery bristles covering the chest and limbs of crustaceans. According to scientists, many filamentous bacteria live in the bristles. These bacteria purify water from toxic substances, emitted by hydrothermal vents, next to which "yeti crabs" live. And there is also an assumption that these same bacteria serve as food for crabs.

This fish inhabiting the coastal waters of the Australian states of Queensland, New South Wales and Western Australia is found on reefs and in bays. Due to its small fins and hard scales, it swims extremely slowly.

Being a nocturnal species, the Australian pine cone spends the day in caves and under rock ledges. So, in one marine reserve in New South Wales, a small group of cones was registered, which hid under the same ledge for at least 7 years. At night, this species leaves its shelter and goes hunting on sandbars, illuminating its path with the help of luminous organs, photophores. This light is produced by a colony of symbiotic Vibrio fischeri bacteria that have settled in photophores. Bacteria can leave photophores and just live in sea ​​water. However, their luminescence dims a few hours after they leave the photophores.

Interestingly, the light emitted by the luminous organs is also used by fish to communicate with relatives.

The scientific name of this animal is Chondrocladia lyra. It is a species of carnivorous deep-sea sponge, and was first discovered off the California coast at a depth of 3300-3500 meters in 2012.

The sponge lyre gets its name from its harp or lyre-like appearance. So, this animal is held on seabed with the help of rhizoids, root-like formations. From their upper part stretches from 1 to 6 horizontal stolons, and on them vertical "branches" with spatulate structures at the end are located at an equal distance from each other.

Since the lyre sponge is carnivorous, it captures prey, such as crustaceans, with these “branches”. And as soon as she manages to do this, she will begin to secrete a digestive membrane that will envelop her prey. Only after that, the lyre sponge will be able to suck in the split prey through the pores.

The largest recorded sponge-lyre reaches almost 60 centimeters in length.

Living in almost all tropical and subtropical seas and oceans, clownfish are one of the most fast predators on the planet. After all, they are able to catch prey in less than a second!

So, having seen a potential victim, the "clown" will track it down, remaining motionless. Of course, the prey will not notice it, because the fish of this family usually resemble a plant or a harmless animal with their appearance. In some cases, when the prey comes closer, the predator will begin to move the esca, an outgrowth of the anterior dorsal fin that resembles a "fishing pole", which makes the prey even closer. And once a fish or other marine animal gets close enough to the clown, it will suddenly open its mouth and swallow the prey in just 6 milliseconds! Such an attack is so lightning fast that it cannot be seen without slow motion. Incidentally, the volume oral cavity fish while catching prey often increases 12 times.

In addition to the speed of clownfish, an equally important role in their hunting is played by the unusual shape, color and texture of their cover, allowing these fish to mimic. Some clownfish resemble rocks or coral, while others resemble sponges or sea squirts. And in 2005, the Sargassum sea clown was discovered, which imitates algae. The "camouflage" of clown fish can be so good that sea slugs often crawl on these fish, mistaking them for corals. However, they need "camouflage" not only for hunting, but also for protection.

Interestingly, during the hunt, the "clown" sometimes sneaks up on prey. He literally approaches her using his pectoral and ventral fins. These fish can walk in two ways. They can alternately move their pectoral fins without using the pelvic fins, or they can transfer body weight from the pectoral fins to the pelvic fins. Gait in the latter way can be called a slow gallop.

Dwelling in the depths of the northern part Pacific Ocean smallmouth macropinna has a very unusual appearance. She has a transparent forehead, through which she can look out for prey with her tubular eyes.

A unique fish was discovered in 1939. However, at that time it was not possible to study it well enough, in particular the structure of the cylindrical eyes of a fish, which can move from a vertical position to a horizontal one and vice versa. This was only done in 2009.

Then it became clear that the bright green eyes of this small fish (it does not exceed 15 cm in length) are in the head chamber filled with a transparent liquid. This chamber is covered by a dense, but at the same time elastic transparent shell, which is attached to the scales on the body of the small-mouth macropinna. Bright green color fish eyes due to the presence of a specific yellow pigment in them.

Since the small-mouthed macropinna is characterized by a special structure of the eye muscles, its cylindrical eyes can be both in a vertical position and in a horizontal position, when the fish can look straight through its transparent head. Thus, the macropinna can notice the prey, both when it is in front of it, and when it swims above it. And as soon as the prey - usually zooplankton - is at the level of the fish's mouth, it quickly grabs it.

These arthropods, which are not actually spiders or even arachnids, are common in the Mediterranean and Caribbean Seas, as well as in the Arctic and Southern Oceans. Today, more than 1300 species of this class are known, some of which reach 90 cm in length. However, most sea spiders are still small in size.

These animals have long legs, of which there are usually about eight. Also, sea spiders have a special appendage (proboscis) that they use to suck food into the intestines. Most of these animals are carnivorous and feed on cnidarians, sponges, polychaete worms and bryozoans. So, for example, sea spiders often feed on sea anemones: they insert their proboscis into the body of an anemone and begin to suck in its contents. And since sea anemones are usually larger than sea spiders, they almost always survive such “torture”.

Sea spiders live in different parts world: in the waters of Australia, New Zealand, off the Pacific coast of the United States, in the Mediterranean and Caribbean seas, as well as in the Arctic and Southern oceans. Moreover, they are most common in shallow water, but can be found at a depth of up to 7000 meters. Often they hide under rocks or camouflage themselves among algae.

The color of the shell of this orange-yellow snail seems very bright. However, only the soft tissues of a live mollusk have this color, and not the shell. Usually Cyphoma gibbosum snails reach 25-35 mm in length, and their shell is 44 mm.

These animals live in the warm waters of the western Atlantic Ocean, including the Caribbean Sea, the Gulf of Mexico and the waters of the Lesser Antilles at a depth of up to 29 meters.

Living at shallow depths in tropical and subtropical seas, mantis shrimp have the most complex eyes in the world. If a person can distinguish 3 primary colors, then the mantis shrimp - 12. Also, these animals perceive ultraviolet and infrared light and see different types light polarization.

Many animals are able to see linear polarization. For example, fish and crustaceans use it to navigate and locate prey. However, only mantis shrimp are able to see both linear polarization and the rarer, circular polarization.

Such eyes enable mantis shrimp to recognize different types corals, their prey and predators. In addition, during the hunt, it is important for cancer to deliver accurate blows with its pointed grasping legs, which is also helped by its eyes.

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4 Giant Sea Spider (Pantopod)

Giant marine Spiders are a relatively little studied group of organisms. And they are only indirectly related to spiders. pantopods They are called sea spiders only for their external resemblance, in fact they are not spiders.

pantopods widely distributed in the oceans. They live as northern seas, and in the south. Some of their species can be found in the surface layer of water, and some sea spiders have been found even at a depth of 7300 meters.

The structural features of these animals include a large difference in the length of the body and limbs. For example sea ​​spider with body size 15-18mm. has limb length up to 240mm. cephalothorax pantopods consists of 7-9 segments, followed by a rudimentary abdomen.

Because of their disproportionately small body, some internal organs pantopod are on their limbs.

sea ​​spiders are predators. They feed on the soft tissues of sea anemones, sponges, and hydroids.

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3. Vespa mandarinia (Giant Asian Hornet)

This Asian giant is one of the most dangerous animals on this list for humans. - the largest hornet in the world. The body length of an average male is 51mm, and the wingspan is 75mm. These giants live in Southeast Asia - in Primorye, in Japan, China, Korea, Nepal, India and in the mountainous regions of Sri Lanka.

The bite of this hornet can be fatal to humans. has a sting about 6 mm long, which stings with discharge a large number poison. The venom of these hornets is highly toxic. But hornets rarely use their sting. Hornets hunt with the help of powerful jaws, with which they tear their prey.

They feed in the same way as their smaller counterparts from the genus Vespa - their diet consists of various insects, fruits, berries. Hornets do not disdain the meat of fish thrown ashore.

They cause great harm to beekeepers. Just a few hornets can easily and quickly destroy an entire bee family. Beekeepers quite often suffer from invasion giant hornets suffering huge losses. Therefore, whenever possible, beekeepers try to destroy hornet nests. During the destruction of the nest, the hornets defend themselves fiercely, biting and stinging people. It is among the beekeepers that the mortality from the bites of giant hornets is very high - dozens of people die every year in the world.