What is a caddisfly and where does it live? Caddisfly insect

Adult insects resemble small or medium-sized (body length 2-40 mm) dimly colored moths. The oral apparatus of the sucking type is poorly developed in species of our fauna and is represented by a short proboscis. The mandibular palps, located on the sides of the oral apparatus, are usually clearly visible. The last segment of the palp can be greatly elongated and divided into rings, although this ringing is not always clearly expressed. Based on this characteristic, the order is divided into two suborders - Annulipalpia and Integripalpia. Large eyes occupy the entire lateral surface of the head. Large lateral simple ocelli are located close to the edges of the compound eyes; their silvery optical lenses point to the sides. The median (frontal) ocellus is located between the bases of the antennae and is directed forward. Often all three ocelli or only the frontal one are absent. The length of the antennae is often approximately equal to the length of the fore wings, less often noticeably shorter, as in small caddis flies or hydroptilids (Hydroptilidae), or significantly, several times longer, as in thin-whiskered caddis flies (Leptoceridae). The forewings are quite densely covered with hairs (hence the name of the order). In addition to hairs, many species also have scales on their wings, reminiscent of butterfly scales. But unlike the latter, the scales of caddis flies never form a continuous cover on the wing, but only spots and stripes. The legs are long (especially the second and third pairs), covered with hairs and setae. In addition to the bristles, the shins of the legs have large movable spurs. Their number and location are of utmost importance in determining caddisflies to family and, in some cases, to genus.

Worldwide distribution. There are about 10 thousand species in the world fauna, in Russia - at least 600. Caddis flies have been known in the geological record of the Earth since the end of the Paleozoic, when the order was represented mainly by now extinct species.

The transformation is complete. The clutch of caddisflies is a gelatinous mass in which from several tens to hundreds of eggs are immersed, and has the shape of a cord or ball. Often both ends of the cord are attached to the substrate, so that the masonry is closed in a ring. Most species of caddisflies lay eggs by dropping them into the water, but there are species in which the females can move along aquatic plants to the depths and there attach the eggs to underwater objects. When it comes into contact with water, the material of the masonry swells, and it increases in size by 3-4 times. After about two weeks, tiny larvae emerge from the eggs, remain in the gelatinous mass for several days and feed on it, and then go into the water. Caddisfly larvae have large heads, small eyes, tiny antennae (often embedded in antennal fossae) and gnawing mouthparts. The legs are walking type, rarely the hind legs are swimming. On the abdominal segments of many caddisfly larvae there are tracheal gills, through which the larva breathes. In “gillless” species, respiration occurs through the integument of the body. But even larvae with gills on their bodies have special “respiratory fields” where intense oxygen absorption occurs. At the end of the abdomen there are two so-called false legs (or trailers); the leg looks like a short stem with a strong claw at the end. The presence of such legs is a characteristic feature of the order of caddisflies.

The division of caddisflies into two suborders is more clearly expressed in larvae than in adults. In the suborder Annelididae, the larvae live freely or in portable, bag-shaped houses; Some free-living forms construct fixed elongated galleries-tubes or trapping nets and chambers. The larvae of the suborder of the entire palpate live in tube-shaped portable (rarely attached to bottom objects) houses, which they construct from a wide variety of building materials - from grains of sand and pebbles to empty shells of mollusks and pieces of aquatic plants or leaves that have fallen into the water. The complex construction activity of caddis flies is possible due to the fact that the larvae have developed powerful spinning glands, the excretory duct of which opens at the tip of the lower lip. The secretion of the gland is a viscous sticky liquid that hardens in water in the form of a strong brownish thread. The strength of the web thread is so great that many caddisfly houses are preserved in collections for decades without falling apart.

With rare exceptions, caddisfly larvae live in water, inhabiting a wide variety of water bodies, flowing and standing (including deep puddles on forest roads), with fresh and slightly salted water. Their diversity and numbers are higher in areas with a fairly humid climate and an abundance of water bodies.

The larvae of caddisflies feed very variedly. Some are filter feeders-detritus feeders, others scrape off fouling, which is so rich in the underwater world of fresh water bodies, others are typical predators or have a mixed diet, often changing their diet depending on the season; there are species whose main food is tissues of living plants. During the larval stage, caddis flies molt several times (usually 4, less often 5-6). Having completed its development, an adult larva from the suborder of the annelids builds itself a durable pupal house - a cave, where it pupates in a cocoon. The larva of the suborder unipalpiformes modernizes its portable house, covering both openings of the tube with a mesh of spider thread, often interspersed with particles of the usual building material, and attaches it to the substrate. They pupate with or without a cocoon. When the pupa is ready to molt into an adult, it breaks through the arachnoid cocoon, as well as the entrance hole of the pupal house, climbs out of it and rises to the surface of the water, where it swims quickly. Having found a suitable object to climb on, or having reached the shore of a reservoir, the pupa climbs out of the water and soon a gap forms on the dorsal side of its head and chest, from which first the chest, then the head, and then the entire insect protrudes.

Adult caddis flies usually stay close to water bodies, often lead a twilight-nocturnal lifestyle and fly to the light in large numbers. Many do not feed at all or lick up loose fluids on plants, including drops of dew or rain. There is evidence that some species feed on nectar and pollen. Male caddisflies (Hydropsychidae) swarm, forming quite large aggregations in the air.

Caddis flies are a favorite food of many fish species, including commercial ones, in particular, a number of sturgeon and whitefish. The larvae serve as food for domestic and wild waterfowl and birds closely associated with water. For example, the dipper pecks caddisfly larvae from the rocky bottom of small streams. Ground birds and other animals readily eat caddisflies during their mass flight. Particularly vivid pictures can be seen on Lake Baikal. In the spring, some species of caddisflies appear there in such quantities that all the shores of the lake, stones and trees turn black from the small caddisflies densely clinging to them. At this time, caddis flies are eaten by frogs, lizards, foxes and even bears, and some species of birds nesting there feed their chicks almost exclusively on caddis flies. Some herbivorous species cause minor damage to rice crops. During the period of mass summer, caddis flies can greatly bother people, flying into rooms into the light through open windows.

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Hello friends! Today I want to continue the conversation about insects that are of great interest to anglers and I want to talk about such a popular insect among anglers as the caddisfly.

Probably many people remember from childhood how they caught crawling houses in clear water in childhood, and the caddisfly reminds many of us of this very house, and few people imagine at this moment a butterfly that is usually small in size and not brightly colored, similar to night moths.

However, a caddisfly is such a butterfly, and crawling houses are caddisfly larvae that always live in water.

Caddisfly – (lat. Trichoptera) a detachment of insects with complete metamorphosis (transformation).

The life cycle of a caddisfly, unlike a mayfly, is complete and can be described by the following scheme: egg - larva (larva) - pupa (pupa) - adult insect.

The difference between the caddisfly and many butterflies is that its body and especially the front wings are covered with hairs, and not scales like those of butterflies. Hence the name Trichoptera: thrix - hair and pteron - wing.

Let's look at the development of the caddisfly in order. The female lays eggs in the water slightly differently depending on the species. Basically, females descend into the water from the shore or dive to the bottom and lay eggs there, but some species can do this on the surface of the water or plants, but in any case, caddis eggs fall to the bottom of the reservoir and larvae (larvae) appear from them.

The larvae of many caddisfly species live in houses that are built from sand, small pebbles, plant remains and other materials. These caddis flies are known to many anglers. Often such larvae are collected and fish are successfully caught with them, both in winter and summer. Few people know that some species of caddisflies build shelters among stones from silk threads secreted by special glands. And some species of caddisflies do not build any houses, but simply crawl between the stones.

And so we figured out that all caddisflies are divided into three groups: those that build houses, those that live freely and those that weave nets from silk threads, building shelters for themselves. In this regard, the features of their life and place of residence may differ.

I will not describe the life features of various caddisfly larvae so as not to clutter your brain; for those who are very interested in these features, you can find a lot of such information in works on entomology.

Regardless of the type of caddisfly, in order for a larva to develop into an adult insect, it must go through the pupal stage (pupa). Those larvas that had houses attach them to stationary objects in the water and plug the holes, and those that did not have houses have to build themselves shelters from sand and small pebbles.

After the caddisfly larva has taken refuge in its shelter, it begins to weave a silk cocoon. Then this cocoon hardens and inside it the larva transforms into an adult insect.

At this stage of metamorphosis, the larva grows wings and the body shape changes, as well as legs and antennae (antennae).

After an adult insect has formed in the cocoon, the caddis fly chews the cocoon and rushes to the surface of the water. At this moment, the caddisfly is still in a transparent shell, which bursts when it reaches the surface. In this state, the insect is very vulnerable and is eaten in large quantities by fish.

The emerging adult caddisfly insect rushes to the shore to a safe place.

An adult insect has two pairs of wings, which are covered with small hairs, as is the whole body. When the caddisfly is resting, the back pair of wings are located under the front ones, and the front ones are folded on the sides of the insect and cover it from above in the form of a house.

The antennae of the caddisfly are long and usually exceed the length of the body.

The caddisfly feeds on the nectar of plants on the shore, but every day they fly to the reservoir to drink water, where they fall into the mouth of a voracious fish.

The silhouette of all caddisfly species is similar and usually has a brown color with various shades. Fly fishermen have long learned to copy the silhouette of an adult caddisfly, and the variety of flies is simply enormous.

Among them there are flies that are very popular, such as “ELK HAIR CADDIS”. I fished very successfully with this fly last season.

There are also a large number of flies that imitate all stages of caddisfly development, and not just the adult insect. Imitation of caddis fly is also successfully used in ice fishing.

At the bottom of many freshwater bodies - clean, fast streams and overgrown ponds - you can find amazing creatures that live in tubular houses that they construct from various small particles lying at the bottom. Depending on what small objects lie at the bottom, and depending on the type of insect, houses can be built from different materials. For some, this structure is made of large grains of sand, for others, it is made of pebbles or shells of small mollusks, often it is a tube consisting of small fragments of twigs or dead parts of aquatic plants, etc. The “building material” is firmly held together by spider threads. These houses are built by caddisfly larvae.

Adult caddisflies are rather delicate insects, similar to hairy moths (Fig. 310). The easiest way to distinguish a caddisfly from a butterfly is by its wings - butterflies have wings covered with scales, while caddisflies have hairs. When at rest, their dark-colored wings are folded like a roof on their back. The head is quite large with compound eyes and usually with 3 simple ocelli between them.

The antennae are long, thread-like, the oral organs are reduced, in particular there are no mandibles at all, and the remaining oral parts are transformed into a short proboscis with a tongue. Adult caddisflies do not feed, but can drink water. The legs, ending in 5-segmented tarsi, are quite slender. These generally inconspicuous, inconspicuous insects fly reluctantly and sluggishly.

After mating, female caddisflies lay gelatinous lumps of eggs called “spawn” in the water. The eggs hatch into larvae, which in most species immediately begin to build an arachnoid sheath from a silk thread secreted by modified salivary glands. The cap is encrusted with suitable small particles lying on the bottom and accessible to the larva. Including hard objects in the case makes it stronger and stronger. And reliable protection is necessary for the caddisfly larva. The fact is that it never leaves the water and breathes through the entire surface of the skin of the entire elongated abdominal section of the body. The abdomen of caddisfly larvae not only has very thin, easily permeable (and if so, easily vulnerable) integument, but often also bears numerous even more delicate gill outgrowths, increasing the surface of gas exchange with water. Bundles of gills are also found on the posterior parts of the chest.

If everything around is calm, the larva crawls along the bottom, carrying the cover on itself. When moving, the larva protrudes its head and thoracic region from its case, on which there are 3 pairs of rather long and tenacious legs extended forward. However, the front legs are often shorter than the rest, and some caddisfly larvae have only two pairs of legs. The head and thoracic segments protruding from the cap have dense coverings. The head of caddisfly larvae is amazing - there are no antennae on it. The larvae of different insects with complete metamorphosis have antennae of different lengths, but they are rarely reduced to such an extent that they become completely indistinguishable, as happens in caddisfly larvae. The eyes of the larvae look like dark spots and consist of several simple ocelli (no more than 6 on each side of the head). The oral apparatus of larvae, in contrast to adult caddis flies, is well developed and gnawing. The larvae feed on both plant foods, scraping soft tissues with serrated jaws, and animal foods. The cap serves the caddisfly larva not only as a permanent armor that protects the abdomen, but also as a refuge: in case of danger, the entire larva is drawn into the “house”, the entrance hole of which is closed with its dense and durable smooth head capsule. The posterior end of the body of the caddisfly larva is held in the case by a pair of powerful hook-shaped processes directed forward. Therefore, the larva can quickly hide in the cover. Holding the house with hooks, the larva drags it along with it, without losing it and only completing it as it grows.

What caddisfly larvae are easy to find in our reservoirs?

In fast streams with cool water and a rocky bottom, tube houses are easy to spot under rocks stenophile(Stenophylax stellatus), constructed from large grains of sand neatly attached to each other (Fig. 311, 1). The larva easily lifts its house, the front edge of which hangs like a hood over the larva’s head, making it invisible to fish swimming from above. If the larva's cover is damaged, it immediately tries to repair it, picking up grains of sand of the required size with its front feet. She fits them to the damaged edge of the cover, discards those that fit less tightly, testing and selecting the most suitable ones. The larva glues the grains of sand with saliva that hardens into a silky thread, wraps them repeatedly with threads, binding the grains of sand to each other, as a result of which the case turns out to be very durable. After repairing the walls of the house, the larva carefully lines its inner surface with several layers of silk cobwebs. If the larva is carefully removed from the case and placed in a vessel, on the bottom of which beads are placed instead of sand, it will make itself a house of small bright beads. Stenophila larvae feed on both plant and animal foods.

In lakes into which streams flow, larvae live in more open places at the bottom apathania(Apatania). Their houses are shaped like a horn (Fig. 311, 4). Larger grains of sand are embedded in the sides of the apatania house.

In shallow sandy places, larvae make their houses built from grains of sand. Molanna(Molanna angustata). Molanna's house, when viewed from above, is wide and flat. The central tubular part, in which the larva sits, is made of larger grains of sand, but attached to its sides are wings made of smaller grains of sand and the same hood. In general, the cover has the appearance of a rather large shield, its length is more than 2 cm (Fig. 311, 5). The molanna larva with its case moves in jerks.

Larvae live in dense thickets of plants freeganei(Phryganea), making their tubular houses from gnawed quadrangular pieces of plants, like short planks (Fig. 311, 5). Often such houses even retain their green color - pieces of aquatic plants in water remain viable for a long time. Freegans have a spacious and long house, the larva can run freely in it. The rear end of such a tube house is open, and if the larva is pushed out of the case, it will quickly run along its surface and deftly duck into it from the rear end. Freeganea is a large insect, the length of an adult larva is about 4 cm. Although the larvae of freeganea, when making caps, bite off pieces of plants and, if necessary, especially in summer and autumn, sit mainly on a plant-based diet, they are not vegetarians. Freegan larvae are more likely to eat mosquito larvae and other small invertebrates.

Larvae are common at the bottom of overgrown ponds limnophiles(Limnophilus). The houses of some species of limnophiles are quite similar to each other. The larva builds a house from various hard small objects lying on the bottom. There may be small swollen sunken sticks, small shells of mollusks, needles, and other plant remains, but pebbles and grains of sand are not used by limnophiles. If the limnophila larva is expelled from the house and the house is removed, it, releasing sticky spinning threads and spinning restlessly, first makes a temporary house out of anything, and then, feeling that the abdomen is somehow protected, begins to make a permanent house, carefully selecting durable particles and fitting them well together.

Common in North America snail caddisflies(family Helicopsychidae), making spirally convoluted cases for themselves, so similar to snail shells (Fig. 311, b) that even zoologists, before confidently saying whether they have encountered a shell or a caddisfly house, must take a very careful look.

Although caddisfly larvae are very well adapted to life in water, among the forms that build cases there are also those that left the aquatic environment and moved on to life on land. That's how land caddisfly(Enoicyla pusilla), living in beech forests of Western Europe (Fig. 312). Interestingly, the females of this caddisfly are wingless. The larvae of land caddisfly live in the litter and among the moss covering tree trunks. This larva avoids water and, when the layer of fallen leaves becomes very wet after heavy rains, moves to tree trunks. The larva makes a house from small pieces of fallen leaves.

Although life in cases is typical for most caddisfly larvae, representatives of some families lead a different lifestyle, despite the fact that they have well-developed spinning glands. In shallow and slow-moving rivers, in thickets of pondweed and other aquatic plants, there are delicate, barely noticeable transparent tubes attached to aquatic plants (Fig. 313).

They vibrate with streams of steadily flowing water. Usually there are many such tubes in one place - a whole cluster. They are made by larvae neuroclip(Neureclipsis bimaculata) from polycentropid family(Polycentropidae). If these tubular formations are transferred to still water, for example placed in a bucket of water, they will collapse and become inconspicuous - the flow of water inflated and maintained the shape of these thin underwater nets. If you look at such a tube through a binocular, you can see that it is indeed a network - a network, remarkably woven, with small cells of the same type. These tubular networks are weaved by narrow, long larvae that live without a cover and do not have gills. The larvae (Fig. 314) build themselves in flowing water not houses, but nets - trapping nets, into which small crustaceans, mayfly larvae and other animals carried by the current fall, becoming prey for the neureclipse. In the water, the predatory larva of this caddisfly catches prey in the same way as web spiders do on land!

In large lowland rivers - in the waters of the Volga, Don, Dniester - many caddis flies develop hydropsychides(family Hydropsychidae). The larvae of hydropsychids make a snare with rectangular cells, and they themselves sit nearby in a light cover made of thin threads (Fig. 315).

As soon as a small crustacean or insect gets caught in the snare, the predatory larvae (their sizes reach about 2 cm) jump out of the shelter and grab the prey with their strong jaws!

Larvae make trapping nets in the form of bags (Fig. 316). plectronemia(Plectrocnemia). It is interesting that such specialized hunters of aquatic prey as hydropsychidae and plectronemia can also go to land. These larvae were found at a distance of tens of meters from streams in the forest floor, where they lived, of course, without making any trapping nets.

However, some caddisfly larvae (family Rhyacophilidae) do not make complex structures in water. Beautiful greenish-blue larvae crawling along the rocky bottom of clean, cold streams riacophile(Rhyacophila nubila), (Fig. 311, 7), reaching a length of 2.5 cm, only release a thread that keeps the larva from being carried away by water. These predators cling to the bottom and to the thread they secrete with their legs and attachment hooks at the rear end of the abdomen and wait for prey. The rapid grasping of prey by rhyacophila larvae is helped by the fact that their strong jaws are directed straight forward, like the predatory larvae of ground beetles.

The development of caddisflies usually lasts 1 year, but in large northern species it lasts 2-3 years.

Familiarization with even a few representatives of caddisfly larvae shows how diverse their habits and characteristics are. But adult caddisflies do not feed, they only reproduce, and they all lead a similar lifestyle. Therefore, it is clear that it is relatively easy to recognize caddisfly larvae (not only the lifestyle of different species is different, but also the structure of individual parts of the body is different), and the species of adult caddisflies can only be recognized by entomologists who specifically study them.

Acquaintance with caddis flies also shows that not only the study of the structure of different parts of the animal’s body makes it possible to distinguish and recognize them well, but also behavior (expressed, for example, in the construction of covers of one form or another) can be used by taxonomists as a reliable sign. The founder of comparative zoopsychology, Russian zoologist V. A. Wagner, first drew attention to this.

There is a lot of peculiarity in the life and development of caddisflies. In most insects with complete metamorphosis, the pupa is almost motionless and, if the larva and the adult insect live in different environments, the larva before pupation makes it easier for the adult insect to find favorable conditions for it, for example: larvae adapted to life in water, such as the larvae of swimming beetles, Before pupation, they emerge from the water and burrow into the ground. Caddisflies behave differently. Their pupa begins its life in a case constructed while still in the larval stage, then it lives freely in the water column for some time, and the last stage of the pupa’s life, before its transformation into an adult insect, occurs in the air.

The pupa of caddisflies is free (Fig. 317). This is generally the same stage adapted to life in water as the larva. The life of a pupa can easily be traced using the example of a stenophila, from whose consideration the acquaintance with caddisfly larvae began. Before pupation, the larva selects a calmer area of ​​the reservoir and, attaching the cap to a stone, braids its ends so that each has a hole for free access of water. When the larva pupates, the pupa inside the cap makes oscillatory movements all the time, resting against the wall of the cap with an outgrowth at the base of the abdomen. To clean the holes, pupae have strong bristles on the upper lip and cleaning processes at the rear end of the body. By the time of maturation, the pupa breaks through the front end of the cap with its powerful serrated jaws (unlike the larval ones, and even more so the practically absent jaws of adult caddis flies) and, emerging from it, begins to quickly swim on its back, like smooth bugs, making rowing movements long, equipped swimming hairs of the middle legs. Having reached a stone, shore or plant, the pupa clings to it and crawls out of the water. It is difficult to call a caddis fly pupa a “resting stage”, as insect pupae are often called!

In the air, the pupa begins to move its abdomen regularly, its spiracles open, its body swells, and the final molt occurs—an adult winged caddisfly emerges through a longitudinal slit on the dorsal side of the chest and head. Those caddis flies whose larvae do not live in covers build themselves covers before pupation. The lifestyle of the pupae is quite similar.

The bottom of many clean fresh water reservoirs is covered with insects that resemble nightlife. They belong to a special order of insects and are called caddis flies.

Adult caddisflies bear a striking resemblance to night moths. Scientists have long been interested in these strange creatures. They described more than a thousand of their species, which were divided into dozens of families and hundreds of genera, and spread over the entire earth's surface with the exception of the cold climatic conditions of Antarctica and some oceanic islands.

Features and habitat of the caddisfly

In all its external characteristics, an adult caddisfly resembles a moth with a dull gray and brown color. There are small hairs on the front wings of this insect; it is thanks to them that the caddisfly differs from.

Butterflies have scales on their wings instead of hairs. On photo of caddisfly and in real life he is absolutely unattractive. Its wings in a calm state are folded like a roof on the back.

A rather large head with eyes and rather long mustaches that look like threads stands out well against this background. You should pay special attention to the eyes of this creature. He has more than the usual norm - 2 compound eyes on the sides of the head and 2-3 auxiliary ones, which are located at the top or in front of the head.

Instead of a mouth caddis insect a proboscis with a tongue was formed. The whole head is covered with warts, which create a not very pleasant sight. Their legs are slender and not very strong.

They can be seen anywhere and everywhere. Your name caddis fly received because he prefers to live in shallow and clean bodies of water. They are comfortable in streams, ponds, lakes, and in some cases swamps, but not too polluted. A clean environment is very important for order of caddisflies.

Mating process of caddisflies

Caddisfly larvae Very similar to mayfly children in that they are also forced to live in water during their development. In order to make it convenient for them to live there, they build houses for themselves, which are practically one piece with their body.

This cocoon is firmly attached to the insect larva. They have to move around with this house on themselves. Anyone who has tried to remove a larva from its hiding place knows that this is a difficult task.

And it is generally impossible to maintain its integrity. But there is a secret how to lure him out of there. It is enough to simply adjust it from behind with something sharp and thin. In order to build a house, the larva uses a variety of building materials, even broken glass.

An unusual experiment was conducted. They took a caddisfly larva and placed it in a clean pond, where, apart from the larva, clean water and broken glass, there was nothing. The larva had no choice but to build itself a glass house.

The photo shows a caddisfly larva in a cocoon

Learned original, creative and comfortable housing. Such a transparent house made it possible to observe how water constantly passes through the gill of the larva. Gills in the form of white threads are located on the back and sides of this interesting creature. Whatever the home of the larva of this insect, it always has the shape of a tube.

There is a variety of housing in the form of a horn or a spiral. Caddisfly larvae slowly move along the bottom of the reservoir along with their house, sticking their heads out of it to see everything around them.

And at the slightest danger, the head hides in the house and the movement stops. The house itself is made of materials that simply blend into the bottom and become completely invisible. Every living creature simply needs oxygen. How does the caddis fly larva solve this problem? Everything is very simple and at the same time cunning.

They build their houses from plants in which the process of photosynthesis constantly occurs and thus, merging in work with their house, they provide themselves with the oxygen necessary for their life.

Mormyshka caddisfly is the lightest and most common bait among many fishermen. It is versatile and easy to obtain. good catching caddis falls between mid-May and mid-June.

This is when the larvae are the largest. After this time, the larvae transform into pupae, and subsequently into “butterflies”, which are called caddis fly. In winter, it is a little more difficult to get caddis flies from the bottom of the reservoir.

It is necessary to drill a hole and lower a broom of birch twigs into it, onto which all the caddisfly larvae will crawl. They can be stored for a long time in an ordinary jar with clean water.

Character and lifestyle of the caddisfly

Adult caddisflies live in reeds and grass on the banks of water bodies. In the evenings they form mass flocks and fly out to mate. These flights are quite long and take them a long distance from their place of permanent residence. The distance can be a kilometer or more.

Adults, when the slightest danger arises, emit an unpleasant, foul odor, with which they try to scare away and protect themselves from possible danger. This smell can be heard even if you just pick them up.

Caddisfly species

There are simply a huge number of different species of caddisflies on the earth's planet. They differ in their external characteristics, habitat, character and even nutrition.

For example, not all caddis flies are as harmless as they seem. There are also those who, in search of food, can envelop a large expanse of water with their silken path, into which not only small insects, but also other inhabitants of the underwater world come across.

Each species has its own favorite place of residence. Some people like quiet, clean creeks, while others prefer the bottom of a fast-flowing mountain river. Accordingly, their sizes and colors are completely different.

Caddisfly feeding

Most of all, caddisflies eat the green pulp of aquatic plants. Those predatory caddisflies that use their webs to get food for themselves love various small insects, and. These caddisflies have a very well developed jaw, which helps them cope with prey.

Reproduction and lifespan of caddisfly

The life of an adult insect is not long. It lasts one to two weeks. The life cycle of a caddisfly is divided into four stages. Its development begins with an egg, which turns into a laurel. It passes into the navel and into the limbs into a mature caddisfly.

Fertilized females lay their eggs in different ways, depending on their species and habitat. Most often, eggs are laid on the surface of aquatic plants that originate at the bottom of reservoirs.

Over time, thanks to dew and raindrops, they gradually sink to the very bottom, and after 21 days, caddisfly larvae form from these eggs. The sticky gel protects the eggs from all environmental factors. They gradually swell and turn into laurels, which in appearance resemble thin and elongated worms.

Gradually, the laurels grow and turn into pupae. Adult caddis flies emerge from the pupae after 30 days. Caddis flies are useful not only because they serve as excellent bait for fishing. Most freshwater fish feed on these beneficial insects.

Less common are larvae that do not have caps - the so-called campodeoid larvae. Such larvae are mainly predators, building special trapping nets from thin cobweb threads. Such nets, shaped like funnels, are placed with a wide opening against the current and are attached motionless to aquatic plants, stones and other underwater objects.

Doll

The larva pupates underwater in a case constructed by it. The pupa has the rudiments of wings, very long antennae, large eyes and huge mandibles, with the help of which it destroys the cap. Thin thread-like gills are visible on the abdomen. The pupa may be equipped with long swimming legs. At the rear end of the pupa's body there are long bristles, with which it cleans the hole in the sieve-like cap, which is easily clogged with silt, and thereby provides access to fresh water. The opening of the anterior sieve lid is cleaned with the help of bristles sitting on the upper lip, and also, perhaps, with the help of elongated jaws. To exit the imago, the pupa floats to the surface, rowing its middle legs like oars. Adult insects emerge in about a month.

Classification

Based on the diversity of larvae, two groups of families are distinguished Trichoptera. Group Annulipalpia includes those families of caddisflies whose larvae build nets (serve for catching prey and shelter). Larvae families Rhyacophillidae And Hydrobiosidae I do not form larval cases, but the pupa is located inside a dome-shaped structure made of mineral fragments. Hydroptilidae- the larvae are free-living until the last stage, after which they build a cap, which can be free or attached to the substrate. Pupation occurs inside it. The larvae of the family Glossosomatidae have a cap similar to the caps of other Annulipalpia, however, the larva stretches a transverse thread under the dome, which allows the larva to drag the house. With each new stage, the larva builds a new case, and then a new case is built for pupation. In this case, the thread is removed and the cover is attached to the substrate. Family group Intgripalpia They mostly build tubular covers. The material for construction and type of construction are species-specific. The larva is mobile and completes its house with each larval stage.

• Suborder Annulipalpia
  • Hydropsychoidea: Arctopsychidae- Dipseudopsidae - Ecnomidae- †Electralbertidae - Hyalopsychidae - Hydropsychidae - Polycentropodidae - Psychomyiidae- Xiphocentronidae
  • †Necrotaulioidea: Necrotauliidae
  • Philopotamoidea: Philopotamidae - Stenopsychidae
  • Rhyacophiloidea: Glossosomatidae - Hydrobiosidae - Hydroptilidae- †Prorhyacophilidae - Rhyacophilidae
• Suborder Integripalpia
  • Leptoceroidea: Atriplectididae - Calamoceratidae- Kokiriidae - Leptoceridae- Limnocentropodidae - Molannidae - Odontoceridae- Philorheithridae
  • Limnephiloidea: Apataniidae - Brachycentridae - Goeridae - Lepidostomatidae - Limnephilidae- Oeconesidae - Pisuliidae - Rossianidae - †Taymyrelectronidae - Uenoidae
  • Phryganeoidea: †Baissoferidae - †Dysoneuridae - †Kalophryganeidae - Phryganeidae - Phryganopsychidae- Plectrotarsidae
  • Sericostomatoidea: Anomalopsychidae- Antipodoeciidae - Barbarochthonidae - Beraeidae - Calocidae - Chathamiidae - Conoesucidae - Helicophidae - Helicopsychidae- Hydrosalpingidae - Petrothrincidae - Sericostomatidae- Incertae Sedis
  • Tasimioidea: Tasimiidae
  • †Vitimotaulioidea: Vitimotauliidae
• Incertae Sedis Genera: †Conchindusia - †Folindusia - †Indusia - †Molindusia - †Ostracindusia - †Pelindusia - †Piscindusia - †Quinquania - †Scyphindusia - †Secrindusia - †Terrindusia

Notes

Literature

• Holzenthal R. W., Blahnik, R. J., Prather, A. L., and Kjer K. M. Order Trichoptera Kirby 1813 (Insecta), Caddisflies // Linneaus Tercentenary: Progress in Invertebrate Taxonomy. Zootaxa./ Zhang, Z.-Q., and Shear, W.A. (Eds).. - 2007. - T. 1668. - P. 639-698 (1–766).
• Kjer, K. M.; Blahnik, R. J.; Holzenthal, R. W. 2002: Phylogeny of Caddisflies (Insecta, Trichoptera). // Zoologica scripta, 31: 83–91.
• Schmid, F. 1998: Genera of the Trichoptera of Canada and Adjoining or Adjacent United States. - National Research Council of Canada, Ottawa.
• Ward, J. B. 1999: An annotated checklist of the caddis (Trichoptera) of the New Zealand subregion. // Records of the Canterbury Museum, 13: 75–95.
• A. V. Martynov. Caddis flies (vol. 1). - Leningrad, publishing house of the Academy of Sciences, 1934.