Insects are a large group representing the phylum Arthropoda. They have distinctive features relating not only to structural features, but also to development. In our article, we will consider the process of incomplete transformation and the insects for which it is characteristic.
Meet the insects
Translated from Latin, the name of this systematic unit means "animal with notches". Insects are one of the classes that belongs to the phylum Arthropoda. Their body consists of a head, torso and chest. The characteristic features of insects also include one pair of antennae, six pairs of segmented walking legs. Most members of the class are capable of flight due to the presence of wings, which are derivatives of their covers.
Types of insect transformations
Insects are basically dioecious organisms with internal fertilization. As a result, females lay eggs. They are covered with denseshells, and inside contain a sufficient supply of nutrients.
Their further development can occur in two ways. With complete transformation, a larva develops from an egg, which, according to external signs, differs significantly from an adult individual - an imago. She repeatedly molts and turns into a chrysalis. At this stage, the insect does not feed and does not move. Further, as a result of transformations, an adult insect is formed, which has all the characteristic features of the class.
The opinion that beetles are insects with incomplete metamorphosis is erroneous. The proof of this is the difference between their larvae and adults. Remember what an adult Colorado potato beetle and its caterpillar-like larva looks like.
Insects with incomplete metamorphosis include orthopterans, dipterans, bugs, dragonflies, cockroaches and other orders. What unites them? From the egg, they develop a larva, which in general terms resembles an adult insect. Its growth is also accompanied by molting, since the integuments of insects are not capable of stretching.
Thus, insects with incomplete transformation include orders whose representatives are characterized by the following stages of development: egg, larva, adult organism (adult).
Hydroptera
The most famous representatives of this order are aphids and song cicadas. They have membranous transparent wings and piercing-sucking mouthparts. They live in large colonies that number hundreds of individuals. Homoptera feed only on sapplants that serve as a source of water and nutrients. At the same time, insects cause significant damage to plants, causing the growth of their individual parts.
Bug
Insects with incomplete metamorphosis include bugs or hemipterans. Representatives of this order are easily recognizable by the unpleasant odor that is released by the substances of specialized odorous glands. The name of the detachment characterizes the structure of the wings of its representatives. Their front is thick and the back is soft.
Most hemipterans are predators and bloodsuckers. For example, a bed bug settles in human dwellings, hiding in furniture, folds of linen, under skirting boards and wallpaper during the day. At night, he goes in search of food. Bedbugs pierce human skin, sucking out blood. These injections are accompanied by itching and discomfort. The danger of bedbugs also lies in the fact that they are carriers of dangerous diseases: plague, typhoid, tularemia.
Dragonflies
"The jumping dragonfly summer sang red…". Everyone knows these words from the famous fable of Ivan Krylov. But dragonflies are not so careless and harmless creatures, as the author presents us. Many insects with incomplete metamorphosis are predators. And dragonflies are no exception. They use their fast and agile flight to catch flies, small butterflies and mosquitoes.
Even dragonfly larvae are predators. They live in small fresh water bodies with stagnant water or rivers with a slow flow.flow. The larvae attack the prey passing by: crustaceans, fish fry, tadpoles. They do this with the help of a mask - the lower lip, which can be thrown forward.
Cockroaches
Insects with incomplete metamorphosis also include cockroaches. These "uninvited guests" love warmth and moisture. They feed on food residues, so they often settle in residential premises. You can recognize cockroaches by their laterally flattened body, downturned head and a pair of long antennae. Depending on the species, they can be black or red.
Cockroaches are quite prolific animals. They lay their eggs in special capsules. They are called ootheca. About 40 eggs can be in one such structure at the same time. The rate of their development depends on the temperature. The higher it is, the faster the larva and adults appear.
Mantises
Representatives of this order are predators. Praying mantises have a camouflage coloration. They lie in wait for their prey in a pose reminiscent of a man during prayer with his hands folded on his chest. Hence the name of this species.
Mantises are very voracious. This is especially true for females. In search of food, they attack insects that are much larger than them. Mantises have been known to eat their own larvae after hatching, as well as males after or during fertilization.
Mayflies
To insects with incompletethe champions for the shortest duration of existence also belong to the transformation. Depending on the type of adult, mayflies live for several hours or days. But the larvae that live in the water develop up to three months, during this period they molt about 20 times.
Mayflies have another unique development trait. They are the only insects that have experienced adult molting with wings already developed.
Stoneflowers
These insects are found mainly in the spring, which is why they got their name. They belong to insects with incomplete transformation, since their larvae and adults lead a different lifestyle. They also differ in their habitats. The larvae live in water and feed mainly on algae. At the adult insect stage, they do not feed.
Lice
The peculiarity of lice is that they settle only on individuals of a certain species. These parasites of humans and animals have a flat body with short antennae, devoid of wings. Their walking legs have movable claws. With their help, they are attached to the hairs on the body of the host, whose blood they feed on.
Orthoptera
Insects with incomplete metamorphosis include grasshoppers, mole crickets, locusts, crickets, and ponytails. All of them are representatives of the order Orthoptera. Their common features are gnawing mouthparts and long hind legs for jumping.
So, with incomplete transformation, insects go through the following phases: egg, larva, similar to an adult, adult. ATIn nature, they are represented by several orders. Insects with incomplete metamorphosis include protoptera and homoptera, lice, cockroaches, dragonflies, mayflies and stoneflies.
