Cicada larvae live in the soil and have a pair of powerful digging front legs. Sucking the sap from the roots of plants with mouthparts weakens the tree, makes the branches die and affects the growth of trees. Usually I will stay in the soil for several years or even more than ten years, such as three years, five years, and 17 years. These numbers have one thing in common, they are all prime numbers.

This is because there are few prime factors, which can prevent them from drilling out with other cicadas when they drill out of the soil, competing for territory and food. When it is about to emerge, drill out of the ground at dusk and night, climb to the tree, and then grab the bark to shed its skin and emerge.

distribution range

Distributed in temperate and tropical regions, inhabiting deserts, grasslands and forests. In addition to the species of Lepidoptera, there are periodic cicadas, which appear in midsummer every year. The most famous periodic cicadas are 17-year cicada and 13-year cicada, also called prime cicada. Because the life cycle is a prime number, it will not meet the natural enemies encountered by the previous generation.

Periodic cicadas appear at regular intervals in a certain area, and dozens to hundreds of dark brown cicada larvae emerge from the soil together, which is very spectacular. Some species are easy to distinguish in singing, behavior and morphology.