Icenser

Cand. Biol. Sciences, N.S. The Department of Zoology of the Verse Biology Faculty of Moscow State University Pavel Kvartalnov talks about one unusual winter find on the banks of the Moscow River.

On one of the first days of the New Year, I received an incredible gift. On January 5, I conducted a tour for a group of schoolchildren at the Zvenigorod biostation of Moscow State University. The day before, we walked through the forest, where we tried in vain to look for traces of animals. After long thaws, it was impossible to find fresh traces. We were rewarded with the unexpectedly blossoming flowers of wolf bast.

In the evening it got colder, the snow fell, and the next tour took place in wonderful winter weather. The temperature held around zero, on a fluffy snow in the floodplain of the Moscow River, insects and spiders appeared in many. I carefully bowed over them, looking for a creature that I had long dreamed of getting to know each other.

And on the way to the village of Lutsino, where a high shore covered with coniferous forest approaches almost to the water itself, some small bug jumped in front of me and, falling, folded her legs, pretended to be dead. This was my cherished dream - Icenser! On that day, we met several glaciers, all of them turned out to be males. Unfortunately, there was no time to take good photos.

The glacier is notable, despite its tiny size (its length is only 3.5 mm). This is an insect with a short greenish abdomen, long thin paws, an elongated stigma. Glaciers cannot fly. In the female, the wings are almost invisible, and in the male are turned into curved hooks, rising above the back and carrying spikes along the lower edge.

Glaciers are included in the Mecoptera-Scorpio Flok detachment. The detachment is small, includes about 300 modern species. These insects were extremely diverse at the end of Perm and the beginning of the Mesozoic, then they were replaced by the bickered (Diptera), who came to the scorpions close relatives. In the Moscow Region, Mecoptera is represented by the Scorpioners itself (Panorpa sp.), And glaciers.

Scorpions live both in our forests and in the Tropics of Indochina, occupying a modest niche of scaders: their larvae feed on humus, and adults suck out already dead insects, sometimes stinging them from spider networks. Glaciers (Boreidae) have so far been found only in the northern hemisphere, in the temperate and polar regions, as well as in the mountains of Eurasia and North America, now there are about 24 species.

Like many extremes among terrestrial invertebrates (for example, quietchings), the life of glaciers is associated with habitat in mosses. Larvae living in moss pillows feed on its risoids, adults can suck plant juices from the “leaves” of moss and celaginel-l. However, they also do not disdain dead insects.

Valnichens venerable age: the oldest representatives of the family are known from the Upper Jurassic of Kazakhstan. The current glaciers are real winter insects. Many small animals, wandering on the surface of snow in the thaw, we can, with attentive search, detect in the warm season.

Only two groups of insects living in the suburbs are found in the form of an Imago exclusively in winter-these are glaciers and wingless flies-cheyes (Chionea SP.). The larvae of the glaciers come out of the eggs shortly after the melting of the snow. They are thick, curved, have three pairs of breast legs and look like the larvae of some beetles. They eat, grow, then make themselves a silk chamber where they pupate. The development of the larva, apparently, takes two years.

Adult insects come out of dolls in late autumn, before snow falling. They are active all winter, finally disappear in April. The female lays in small portions of one or two dozen eggs, and then, after a break, fed, she can postpone the same amount. At the scorpions, the male feeds the female before fertilization. The glaciers have lost this behavior. After a short acquaintance with the female, the male of the glacier jumps on her, firmly in the limbs of her girlfriends at the end of the abdominal legs, helping herself with hook-shaped wings. If the jump failed, the female leaves to look for another gentleman. If the male was able to resist, the female becomes passive.

True, in some types of glaciers, the male has to work more, overcoming the resistance of the female trying to run away, drag a gentleman behind him. In this case, the female stops resistance, as soon as the male manages to dodge and squeeze the gonopody-mi of the base of her antennae. The male, with the help of wings and gonopodia, turns the submissive female so that she is sitting on his back, then copulates, and mating can last several hours, up to two days. Sometimes partners diverge, and then mate again. The male can move during mating, firmly holding the limp female by gonopodia.

The winter life of the glaciers passes in a snowdrop space, where constantly high humidity and favorable temperature is held. It is almost impossible to meet mating glaciers on the surface of snow. The Norwegian zoologist Sigmund Hagvar found that the glaciers, like other representatives of the winter ento-nan, go out for the snow for the sake of resettlement. They are selected along the outlets along the trunks of trees and bushes, choose a direction and each move for a long time in their own direction, apparently oriented around the sun.

Most likely, glaciers can capture polarized light, since their migrations occur mainly on cloudy days. Sunny weather for glaciers and other winter insects is insidious: in the evening in a clear sky, the temperature drops quickly, and the glacier can freeze, not having time to hide under the snow. Although substances that prevent it from freezing were found in the hemolymph of the glaciers, these insects do not tolerate temperature to -5 ° C.

Glaciers can slowly move along the snow, but during migrations they move in small jumps, which allows them to reach a speed of about 1.2 m/min and overcome a decent distance. On the surface of frozen lakes, glaciers were found, 50 or more meters from the shore. Glaciers are not afraid of predators: they can distinguish a very smelling, probably poisonous, substance.

In recent years, it has been proven that the glaciers are the next among modern insects of the fleas (Siphonaptra). Fleas appeared in Yura as specific parasites of the ancestors of mammals. They made a good choice and, evolving along with their owners, reached prosperity (at least 25 thousand modern species!). Some switched from mammals to birds. Fleas are known as perfect jumpers. Only recently, scientists decided to check how close the jumping mechanism of fleas and glaciers.

It turned out that in general terms, fleas and glaciers jump similarly, this confirms their relationship. For jumping, the pectoral muscles are used, before the jump, energy accumulates in the bundles of the protein of the rubber. This protein is used by many jumping insects: when the muscles are reduced, the threads of the rubble thread are compressed, and then, instantly straightening up, provide an impetus that lifts the insect into the air.

Such a “catapult mechanism”, which allows to accumulate energy gradually, leisurely reducing muscle fibers, gives the glaciers the opportunity to jump in the cold. If the temperature drops, the muscle contraction time increases, but the jump rate remains the same. The glaciers start with such a loose substrate as snow, they need a reliable support more than fleas.

Apparently, therefore, during jumping, they use not one, but two pairs of legs - the middle and the rear. This is a unique case among insects: most of the "jumpers" are repelled only by hind legs. The impetus with two pairs of legs gives the glacier to the body stability in flight: unlike a flea, it almost does not tumble. Glaciers can give odds to their famous relatives!

I don’t know how well the schoolchildren who were present on the excursions remembered who the glacier is. It is important for me that they experienced the joy of the find with me. Now they will also have their own little dreams, the expectation of a meeting with some animal or flower. If so, then the tour was successful.

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