How long do dragonflies live? Are dragonflies beneficial or harmful?

Dragonflies are the general name of dragonflies and dragonflies of the family Odonata. They belong to incomplete metamorphosis. There are more than 5000 species in the world and more than 300 species in China. Among them, there are many common species of dragonflies, such as Biwei fly, yellow mole and long-leaf mole, etc., so how long can dragonflies live? Is dragonfly a beneficial insect or a pest?

How long can dragonflies live

The larvae of dragonflies spend at least a year in the water, and the time required for the whole larval stage varies according to different species and seasons, ranging from one month to three or four years, and those who take a long time have to endure seven or eight years before they can emerge as adults. Dragonfly adults live only 1/10 of their larvae and only live about 1-8 months. Nevertheless, dragonflies still have a long life among insects.

Is dragonfly a beneficial insect or a pest?

Dragonflies are beneficial insects. Young insects can prey on wigglers or other small animals in the water, and sometimes the same kind also eat each other. Both adults and larvae are carnivorous and eat more pests. Adults can prey on mosquitoes and flies in large quantities. Some can also prey on butterflies, moths, bees and other pests, which are actually beneficial insects. The food intake of dragonflies is also very amazing. A large green dragonfly, commonly known as "Qingtou Leng", can eat about 2000 aphids and other small flies a day. It is said that a horse dragonfly can eat nearly 1000 small flies in a day. It can eat 40 flies or 840 mosquitoes in an hour. At the same time, dragonfly larvae especially like to eat mosquito larvae. A dragonfly larva can eat more than 3000 mosquito larvae a year.

Where did the dragonfly go in winter

Dragonflies have basically completed their entire life cycle before winter, but their eggs will be placed in plants, in dead wood or even in dry soil, or will be dropped on the water, depending on their breeds. the eggs of most temperate dragonfly species do not hatch after birth and may take several months to hatch, a period of non-incubation known as "diapause". The aim is to get dragonflies through the cold winter in the form of eggs.

What kind of food do dragonfly larvae eat?

The feeding habits of dragonfly larvae are related to species. Dragonfly larvae usually inhabit streams and mainly feed on Diptera larvae such as mayfly larvae, stone fly larvae, Chironomus and some small fish. the species inhabiting quiet waters mainly feed on tadpoles, small shrimps, small fish, water fleas, smaller dragonfly larvae, backstroke bugs, chironomids and other Diptera larvae. The larval stage is the longest time in the dragonfly's life. The first stage or age of the hatched larvae of dragonflies is called pre-larvae, which has no feet and usually lasts only a few seconds to a few minutes. After the first peeling, the larvae enter the second age, with simple feet and three jointed antennae. Dragonfly juveniles have different ages according to different species, ranging from 8 to 16 ages, and the time required for the whole larva varies according to different species and seasons. From one month to three or four years.

The above is the introduction of dragonfly habits by the editor of Tuliu.com. The process of adult emergence of dragonfly is very long, and it can eliminate a lot of pests. It is a veritable beneficial insect.