Large crayfish. Large sea cancer: photo and description. Marine hermit crab. crayfish habitat

There are over 70,000 different crustaceans on our planet. They are found in almost all water bodies of the world: in rivers, lakes, seas and, of course, oceans. With all the diversity of crustaceans, even today, not all of their species are well studied by zoologists. One of the most prominent representatives of this subtype of animals are the large sea lobster crayfish, hermit crab and mantis shrimp.

Who are crustaceans?

So it is customary to call a huge group (subtype) These include crabs, shrimps, crayfish, sea crayfish (mantises, hermits, etc.) that are well known to us. Currently, scientists have described about 73 thousand species of these creatures. Representatives of this group of animals have mastered almost all types of water bodies on our planet.

The vast majority of crustaceans are actively moving creatures, but in nature you can also find motionless forms, for example, sea ducks or It is worth noting that not all crustaceans are marine animals, some of them, for example, crabs and wood lice, prefer to live on land.

Lifestyle

Crustaceans, including lobster, mantis shrimp, and hermit crabs, are both large and small within their family and species. Many of these animals are excellent at camouflage, drastically changing their color to match the color of the surrounding ground, such as the blue lobster. As mentioned above, while some crayfish run, swim and climb everywhere, others prefer a passive lifestyle, attaching themselves to certain underwater objects.

Many crustacean creatures protect themselves from enemies with calcareous shells, but not all have this ability. For example, large sea lobster crayfish, as well as shrimp and crabs, do not have shells at all. Their body is covered with a reliable shell, consisting of durable chitinous plates. Such shells are also found in familiar crayfish.

reproduction

Marine crustaceans reproduce by laying eggs. In all large crayfish, they look like fish caviar. For example, lobsters lay their eggs in incredibly large numbers - from 1.5 to 600 million pieces per period. Of course, not all eggs will hatch into crustaceans. The vast majority of them go to feed fish and other marine animals.

So, let's take a closer look at a few of the brightest representatives of the hermit and lobster (lobster) marine crustacean subtype.

mantis shrimp

These animals live at shallow depths in subtropical and tropical seas. Their unique feature is the most complex eyes in the world. For example, if we can distinguish only three primary colors and their shades, then mantis shrimp see a spectrum consisting of 12 colors. Scientists who have studied these animals are sure that they see infrared and ultraviolet colors, as well as different types of polarization of the light flux.

Mantis lifestyle and hunting

The sea mantis shrimp is a rather aggressive creature that leads a solitary lifestyle. It spends most of its time in crevices or in ground burrows. Mantis shrimp leave their shelters only in case of searching for food or changing their habitat. These creatures catch their prey with the help of sharp and jagged segments on grasping legs: during the attack, the marine mantis shrimp makes several quick and powerful kicks on the victim, killing it. Animals feed on both small crustaceans and gastropods. They do not disdain carrion.

Cancer hermit

These creatures have an unusual appearance. It largely depends on where they live. Hermit crabs are chained in a spiral-twisted shell. Outside, only three pairs of walking legs are visible. On the first pair are claws of different sizes. The largest claw plays the role of a plug: with it, the sea hermit crab plugs the entrance to its own shell.

Hermit lifestyle

The name of this species of sea crayfish speaks for itself: they lead a solitary lifestyle. As a dwelling and shelter, most hermits use shells left over from these creatures. These creatures live in tidal zones and at shallow sea depths. Some hermit crabs can leave the water element for a long time, returning to the sea only during their breeding season. Hermits are typical corpse eaters.

Lobster (lobster)

This is a large marine crayfish of the invertebrate family. At first glance, this creature may resemble the well-known crayfish, but there is still a difference between them. All representatives of this family are distinguished by huge pincer limbs. Otherwise, they are very similar to ordinary crayfish.

How to recognize a lobster?

To distinguish a real lobster from one or another large crayfish, you need to pay attention to its claws and legs. The fact is that true lobsters have rather massive claws located on the first pair of legs. On the second and third pair of legs, these animals also have claws, only many times smaller than those on the first. In total, these creatures have five pairs of limbs.

External description of lobsters

Lobster is a marine crayfish that inhabits the vast majority of the water bodies of our planet. Its powerful claws are an indispensable tool for obtaining food and protection from all kinds of sea enemies. Lobsters have three pairs of jaws on their heads. The most powerful are the so-called mandibles, with the help of which crustaceans grind food. The rest of the jaws filter it. By the way, lobster shells are easily cracked open with their large claws.

These creatures eat everything that is of an organic nature, that is, they eat everything that falls into their claws. To do this, they wander for hours on the bottom of the sea. Like all crayfish, lobsters' favorite food is the half-rotted remains of marine animals. They do not disdain small crustaceans, snails, mollusks and other invertebrates.

The eyes of the largest marine crayfish in the world consist of many small and separate eyes called facets. Surprisingly, one eye of a lobster can be made up of 3,000 facets! Only deep-sea crayfish do not have them. The bristles located on the head replace their sense organs. With the help of them, lobsters touch, smell and determine the chemical composition of water.

General description of lobsters

Lobsters, like many marine animals, breathe through gills. They are located under their shell. These creatures prefer exceptionally cool and medium-salty waters, the temperature of which is not higher than 20 degrees Celsius. Lobsters can hardly be found in the seas washing the shores of our country, since their habitat is limited to the Scandinavian Peninsula from the Atlantic.

This marine crayfish has a well-defined sexual dimorphism, i.e. males are always much larger than females. The abdominal region of these animals is quite well developed: all appendages and segments are distinguishable without any difficulty. The chitinous shell of lobsters sheds from time to time.

The musculature of the body in these animals consists of specialized and well-developed muscles. The life expectancy of male lobsters ranges from 25 to 32 years, and that of female lobsters is up to 55 years. According to the Guinness Book of Records, the largest sea lobster was caught in Canada (Nova Scotia). His weight was 20.15 kg.

Lobster behavior in danger

Lobster is a marine cancer capable of injuring himself for his own safety. For example, when the limbs are captured by some enemy, lobsters throw them off without hesitation, that is, they lose their own legs on their own (sometimes up to six at a time). This allows them to evade danger by hiding in cover.

Lost limbs regenerate over time, that is, they are restored. True, the process of their complete restoration can take several years, but what to do - your own life is more expensive. And lobsters are well aware of this.

What is the lobster dying for?

First, lobsters, like other crustaceans, are links in the food chain. In other words, they feed many marine fish (as the main food) and birds. To be honest, lobsters and other crayfish, as well as shrimp, oysters, and crabs are people's favorite delicacy food. It even got to the point that entire factories are currently being built, where crayfish are specially bred for further consumption.

Secondly, lobsters are quite sensitive to the chemical composition of the water. A deadly threat to these animals is the constant pollution of waters with various industrial wastes, slags and other garbage.

Lobsters in cooking

As already noted, in cooking, a large sea crayfish is considered an exquisite delicacy. People eat its meat, which is famous for its tenderness. Meat is eaten from under the shell, as well as from the legs and host of lobsters. In addition, people eat caviar and liver of these animals. Soufflés, soups, salads, aspic dishes, croquettes, mousses, etc. are prepared from crustaceans in restaurants.

Lobster extermination

The population of crustaceans is constantly declining. From the middle of the 19th century, the first attempts were made to breed lobsters in artificial reservoirs. At the beginning of the 21st century, this occupation gained full momentum. However, until now, people have not been able to find a commercially viable method of cultivating sea crayfish.

Crayfish are a subtype of crustaceans, which include the well-known crabs, lobsters (often referred to as marine crayfish), shrimp, and common freshwater crayfish.

Today we will try to figure out whether it is possible to call a lobster a sea crayfish and whether there are differences between it and ordinary crayfish, except that the former live in sea water, while the latter settle in freshwater lakes and rivers. Let's just say that there are differences and not only in size. Sea crayfish has a slightly different body structure from the river, as well as a completely different taste of meat, not to mention the fact that it needs to be cooked in a completely different way.

Lobster Habitat and Food Video

This film tells about such a wonderful marine life as a lobster. What does he eat, to what size can he grow and how long does he live.

Biological classification of freshwater crayfish and lobsters.

Both lobsters and crayfish are typical representatives of the subtype - crustaceans, representing arthropods. Their classification is also the same - these are higher crayfish, and in the same way they belong to the same order - decapod crayfish. Next comes the division into infraorders, from which, in our case, it is necessary to single out Astacidea - which include marine crayfish and freshwater familiar to us.

And only the next step in the classification of these animals is different, namely, they belong to different families. To be more precise, lobsters represent marine arthropods, and multiple varieties of the river are also united in an independent family.

Similarities and differences between crayfish and sea lobster

In their structure, both the first and the second are extremely similar: they have an equal number of tentacles, the first pair of limbs are claws, a hard shell, with brightly defined parts and appendages.

Both in river and sea crayfish, males differ in significantly larger dimensions than females.

Lobster or sea crayfish differs from freshwater crayfish in massive claws. In river boats, with similar hull sizes, they are several times smaller.

In general, almost all types of lobsters are large in size when compared with related inhabitants of lakes and rivers. For example, a huge specimen is listed in the Guinness Book of Records - this is a sea lobster that weighs more than 20 kg. Even the largest crayfish is not able to hold out even up to 10% of this weight.

Another major difference is the environment in which they live. Crayfish live and breed only in fresh water, as a rule, these are rivers, rates, lakes, ponds and streams. Lobsters live only in salt water oceans, seas, lagoons and bays.

How many live

Probably, many do not know, but the arthropods described by us are real centenarians. For example, ordinary cancer survives under favorable conditions up to 20 years, and sometimes more. As for its marine counterparts, the situation here is even more interesting. It is not uncommon for them to live up to 50-70 years, and the oldest lobster, according to fairly reliable information, is more than 100 years old!

Scientists have only recently found a method for determining the age of crustaceans, and we hope that soon we will have more accurate data on how many years these aquatic animals live.

Taste and cooking differences

Other differences between these crustaceans are important only for us. Catch and those and those since ancient times. The taste of crayfish and lobster meat is extremely similar, but there are some differences. Lobster meat, according to experts, is more tender and piquant, while freshwater crayfish taste is not so bright.

However, nevertheless, both the first and the second are valued for their wonderful taste, although sea cancer is recognized as a more refined dish.

They need to be prepared according to completely different recipes.

Crayfish are boiled with the use of various spices, sometimes in beer, but more often with ordinary salt and dill. How much and when to add these ingredients, read the section "Dishes from crayfish".

Sea lobsters can be grilled, baked and boiled as well. Almost no other dishes are prepared from freshwater crayfish, but savory soups and so on are often cooked from lobsters.

Crayfish and lobsters are used to make sauces with a specific flavor of seafood. It is easy to make, you just need to take a decoction and add butter and a little flour to it.

caraway;
black pepper;
fresh dill is better, but dried is also possible;
cloves.

But for cooking lobster you need other spices:

paprika;
Cayenne pepper;
thyme.

Beer is traditionally served with ordinary crayfish and it really is more suitable of all drinks, and wine for lobsters.

This video shows and details how much the regular crayfish cooks and what seasonings will be needed to emphasize, rather than interrupt, the taste of its mouth-watering meat.

The largest freshwater crayfish in the world can be found in the rivers of Tasmania. Even in the recent past, these crayfish could grow up to 80 centimeters in length and more, they weighed at least five kilograms. Now Tasmanian crayfish, on average, have no more than 40-60 centimeters in length and weigh only 3-4 kilograms. And all because these individuals simply do not have time to live to a gigantic size, they are caught.

In Latin, they are called Astacopsis gouldi, until recently, specimens 80 cm long and weighing more than 5 kg were a normal occurrence. Today, such giants are practically not found, and the average parameters of crustaceans are about 50 cm with a mass of 3-4 kg.

Those wishing to see this miracle of nature with their own eyes need to go to the north of the island, where there are slowly flowing rivers and streams with warm (from 18 degrees) and very clean water - this is where giant crayfish are still found.

What do the biggest crayfish eat? The largest crayfish in the world feed on everything that is found in water bodies. These are decaying foliage and wood, fish, as well as aquatic invertebrates. Bypass arthropods platypus, large fish and water rats. All of them are natural enemies of the Tasmanian crayfish.

This animal lies and waits to capture its prey, and its bite can tear off a finger. Having a black shell, the creature merges with the rocky bottom of the rivers and is not so easy to notice either by predators or its prey. But don't worry, they are quite rare.

Astacopsis gouldi are long-lived. Tasmanian crayfish can be up to 40 years old. In addition, these individuals have a very long reproductive process. In males, reproductive age occurs at about 9 years old, in females and even later - at 14 years old. By the way, male crayfish, as a rule, give birth to a "harem" of several females. Well, breeding offspring happens only once every two years. Females lay eggs on their abdominal legs in autumn. And juveniles, whose length does not exceed 6 millimeters, hatch only next summer.

But this photo often goes on the Internet along with Tasmanian crayfish, but in fact it is a palm thief or a coconut crab:

By the way, this type of crayfish has already been recognized as rare, and in Australia they even issued a law that prohibits catching Astacopsis gouldi without special permission. Well, violators will be punished with the ruble. The fine reaches 10 thousand dollars. By the way, the name of the species of crayfish was given in honor of a naturalist from Australia named John Gould.

Scientific classification:
Kingdom: Animals
Type of: Arthropod
Subtype: Shellfish
Class: Higher crayfish
Detachment: Decapod crustaceans
Family: Parastacidae
Genus: Astacopsis
View: Astacopsis gouldi (lat. Astacopsis gouldi (Clark, 1936))

Who doesn't love eating crayfish? Most likely, a rare person in the world does not like the meat of these arthropods, because it is not only very tasty, but also healthy. But everyone is used to the fact that ordinary cancer does not grow more than 5-10 centimeters. But still, in some places in the world there are such specimens that even do not fit in a bag.

Tasmanian crayfish - huge and freshwater

The largest freshwater crayfish in the world can be found in the rivers of Tasmania. They are called Astacopsis gouldi. Even in the recent past, these crayfish could grow up to 80 centimeters in length and more, they weighed at least five kilograms. Now Tasmanian crayfish, on average, have no more than 40-60 centimeters in length and weigh only 3-4 kilograms. And all because these individuals simply do not have time to live to a gigantic size, they are caught.

These crayfish live in the northern part of Tasmania. And they are very whimsical about their home. Arthropods like to settle in shady calm streams and rivers, where the water is very clean and oxygenated with an air temperature of at least 18 degrees Celsius. The reservoirs in which crayfish live, as a rule, flow north and flow into the Bass Strait, there are rivers at an altitude of up to 400 meters above sea level. Crayfish are distinguished by color, which depends on their habitat. So, the color can vary from greenish-blue to brown. However, there are also individuals of an unusual color, for example, blue.

It is not surprising that the largest crayfish in the world are on the verge of extinction. This happened due to the active agricultural activity of man (as a result of which the quality of water in the rivers is rapidly declining and the crayfish are losing part of their habitat because of this) and overfishing from the rivers. By the way, this type of crayfish has already been recognized as rare, and in Australia they even issued a law that prohibits catching Astacopsis gouldi without special permission. Well, violators will be punished with the ruble. The fine reaches 10 thousand dollars. By the way, the name of the species of crayfish was given in honor of a naturalist from Australia named John Gould.

Large live cancer

Parastacid crayfish - the largest cancers of the Southern Hemisphere Another largest type of crayfish is found in the southern hemisphere of the planet. In the same Tasmania, as well as in Australia, Madagascar, New Guinea and Fiji, the so-called parastacid crayfish live, they differ greatly from their relatives in size. Found a monster in Papua New Guinea. Most often you can stumble upon representatives of the genus Cherax. Their length can reach 30 centimeters, weight 2 kilograms. It is noteworthy that such crayfish are visible from everywhere - they are painted exclusively in bright colors. However, the color may vary depending on where you live. Sexual maturity of cancer occurs quite early, at the age of 6-9 months. With powerful claws, these arthropods dig huge holes for themselves, however, quite often they prefer to inhabit ready-made shelters - these are cavities under stones and snags (experts call this species “little digging”).

This type of cancer lives, unlike the previous champion, only five years, or even less. Death overtakes an individual if the water temperature reaches critical levels: below 10 degrees Celsius and above 36 degrees. But these crayfish are undemanding to the quality of water. They can survive even at very low oxygen and relatively high nitrate levels. And the most dangerous for parastacid crayfish is the content of copper in water, even if it is negligible. Arthropods feed, as a rule, on detritus, but they can also eat plant foods, as well as living and dead small animals. Can catch, on occasion, and small fish. At the same time, parastacid crayfish live well in captivity. Therefore, Cherax crayfish can often be found in aquariums. They say that arthropods can travel around the clock

around the aquarium and study it. Crayfish are quite peaceful and can get along with almost all fish, except for aggressive ones. Experts recommend organizing shelters for them in the form of stones, snags or ceramics.

The biggest crab in the world

For comparison, you can estimate the size of the largest crab in the world. They recognized the spider crab. By the way, it is a relative of cancer, at least it is included in the phylum Arthropoda and the subphylum Crustaceans.

The giant crab Macrocheira kaempferi got its name not by chance. The first biologist to publish a description of the creature, a German explorer and naturalist, was named Engelbert Kampfer. It happened in 1727. And since then, Western scientists have been familiar with this giant crab. Well, the arthropod spider crab got its name due to its amazing similarity with the insect of the same name.

The biggest crab in the world

The spider crab wears a shell up to one and a half meters in circumference. The long limbs of an arthropod in a straightened form reach four meters. By the way, the largest claws are found in males - they grow up to 40 centimeters. An adult crab weighs about 20 kilograms, which is significantly more than the weight of the largest cancer in the world. Crab on such huge stilts is found in the Sea of Japan, near the islands of Kyushu and Honshu. And lives at a depth of more than 400 meters.

Spider crab reaches sexual maturity by 10 years. Well, until that time it lives at shallow depths and, often, becomes the prey of predators. Often, the giant Japanese crab is of interest to poachers and becomes a commercial object. That is why the number of miracle creatures is declining every year.
Subscribe to our channel in Yandex.Zen

But this photo often goes on the Internet along with Tasmanian crayfish, but in fact it is a palm thief or coconut crab

sources