Science knows more than three million insects. There are different among them. The meager sizes and morphology of some are amazing! These are micrometers of organisms that can refuse everything except the main thing - sexual desire. Nature is unique. It turns out you can not eat, drink or even go beyond the intended space! The main thing is to wait for the only female who will find you to continue her family, even if her life lasts only a few days.
From larger to smaller
For the first time in Russian sources, an insect, as a word, is found in 1731. It literally means "notched animal." In 1758, the scientific name of this class was introduced. But even among these small representatives of the terrestrial fauna there are the smallest that surprise us with their size. And it seems to us to see them mainly in photographs.
For a long time, it was widely believed that the smallest insects live in forests in the eastern United States. Their name is Nanosella fungi. These are beetle bugs. When scientists entomologists found that the measurements were not entirely accurate, the smallest insect at that time, took its place of honor at number two, among the beetles. But even so, the dimensions of 0.39 mm are such that they allow bugs to live in the fungi where the spore containers are located.
In 1999, science learned about Scydosella musawasensis. This microscopic beetle was recognized in 2015 as the smallest insect among the beetle species. The average length of such an individual is 0.337 mm, and the largest bug has grown to 0.352 mm. The exact dimensions were determined by Russian coleopterologist Alexei Polilov. This beetle also lives in fungi where tubular layers are located. He received his species name in the first place of discovery. It was Nicaragua.
Megaphragma mymaripenne
This is a small parasitic rider with such small sizes that completely determine its lifestyle and structure of the whole organism. His brain is completely devoid of chromosomes, and his life lasts only five days. This species of riders does not grow more than 0.2 mm, and 95% of its nerve cells lack a cell nucleus. It is smaller than ciliates. Distributed in almost all parts of the world, except Antarctica and Asia.
Science does not stand still
At the end of the 20th century (90s), a species of tiny insects called Megaphragma caribea (family Trichogrammatidae) was discovered. Its dimensions do not exceed 0.171 mm. Habitat - these are small islands of Guadeloupe that are located in the Caribbean Sea. It could be argued that this is the smallest insect, if not for another species, accidentally discovered in 1997.
Among parasitic riders, Mymaridae took the lead. They parasitize on bugs, bugs and some aquatic insects. Most of them live in Europe. There are more than 500 species of miramids, some of which scientists have successfully used for biological control of pests.
Here he is - the smallest parasite!
And so, while observing Echmepteryx hageni (USA), the smallest insect was discovered - this is Dicopomorpha echmepterygis. Then they saw females of small riders. Several eggs of a haymaker were opened and a fully formed female and three smallest individuals of the same species (males) were found.
It turns out that the smallest insect in the world (Dicopomorpha echmepterygis) is the host-killing (idiobiont) egg parasites of hayed ones. The remaining eggs contained one female and one male.
Using a scanning electron microscope, it was possible to establish the dimensions of the male parasitic rider, whose length was only 0.139 mm. It belongs to the same family Mymaridae (egg-eating riders). In this species, larvae develop in insect eggs, and its representatives are distributed throughout the world. So it became known to the entire scientific world, what is the smallest insect, its size and habitat.
Characteristics, Features and Reproduction
It turned out that female riders are twice as large as males. They differ in proportions, the number of visible scleritis of the abdomen, antenna segments and the structure of the legs. In addition, females have cirrus wings. They have complex eyes, there are single lenses that respond to the level of illumination, as well as multi-segmented antennas of sufficient length.
Interestingly, the smallest insect on earth (the rider Dicopomorpha echmepterygis) has pronounced sexual dimorphism. Males have no eyes, mouthparts and wings. Its antennas are one segment with a single sensilla and two more on the head capsule. The joints of the legs are fused to the lower leg, and the suction cups replace the claws. Most likely, males are not able to move outside the egg.
The host of the smallest insects is the haymaker Echmepteryx hageni. It lives in the trees of eastern North America and lays eggs in the shallow cracks of the bark. It turns out that the female parasite needs wings to move from one tree to another.
Most likely, the size and morphology of males simplify the search for a sexual partner. They come out of one egg and the female can easily meet her male. So, these individuals are a unique example of miniaturization. The smallest rider does not eat, does not fly, does not drink, does not see. Deprived of almost everything, he waits for the only thing - his female, to complete the breeding task.
It is also known that Alaptus magnatimus, from the same family Mymaridae, has a male body length of only 0.12 mm.
Interestingly, the rider larva easily feeds on the contents of a bug egg. It also pupates inside the egg shell and 15 days after infection, the larva will give an adult winged egg-eating rider.
Visualization for little ones
Today, many children are fond of biology and related sciences. They are interested in knowing not only about the macrocosm, but also want to look into the microcosm. It is far from always possible to use an electron microscope and see the smallest parasites. If this is interesting, then you can find coloring for the smallest. The insects of the smallest species are presented in encyclopedias in biology, entomology.
There are enough images on the Internet. Therefore, if it becomes necessary to show the smallest inhabitants of our amazing planet to children, there is always the opportunity to find appropriate sources for visualizing the story.
Perhaps in the near future, scientists will discover a new species of insects that will surpass those known to us today in their minimum size. These will be the greatest new discoveries that never cease to amaze us.