The synchronized emergence of thousands of cicadas always makes headlines. Called periodical cicadas, the seven species of the genus Magicicada live most of their life cycles underground, appearing for just a few months every 13 or 17 years. Though often called 17-year locusts, this is a misnomer. Periodical cicadas are not locusts at all, and belong to an entirely different order of insects – the Hemiptera.
Adult periodical cicadas have black bodies, and distinctive red eyes. The abdominal segments are striped with orange on the underside. Their translucent wings are webbed with orange veins, each forewing tipped with a black W-shaped marking.
To determine the sex of an adult cicada, simply look at its belly. On the underside of the female abdomen, a groove reveals the ovipositor. The male abdomen ends in a flap, shaped like a square.
Periodical cicadas may be confused with other annual cicadas that emerge at the same time. To identify cicada species, learn their songs, which are unique to each type of cicada.
During their long period underground, nymphs nourish themselves by sucking the juices from plant roots. Adults also feed on plants, choosing fluids from the tender growth on woody vegetation.
During their long stay underground, nymphs go through five stages, shedding their nymphal skins at the end of each stage. In the year of emergence (usually either 13 or 17 years), the nymphs construct tunnels to the surface. Once soil temperatures reach 64 degrees Fahrenheit, the cicadas emerge en masse after sunset and head to the nearest vegetation. They molt a final time to reach adulthood.
The new adults, which are white after emerging, remain on the vegetation for 4-6 days, allowing their new exoskeletons to darken and harden. Once the teneral period ends, males start singing their calling songs. The males aggregate as they sing, creating a deafening sound. Collectively, they move and sing until they find receptive females.
Mated females excavate Y-shaped nests in living twigs on shrubs and young trees. In each nest, the female may lay up to 20 eggs; during her short lifetime, she can lay as many as 600 eggs. Within 4-6 weeks, the adult cicadas die.
In midsummer, eggs hatch. Nymphs about the size of small ants fall to the ground, and burrow in the soil to begin their long stay underground.
Special Adaptations and Defenses:
Periodical cicadas rely on their numbers for defense. With bright coloring and a loud call, a lone cicada would quickly be eaten. When thousands emerge at once, the cicadas can sacrifice some individuals without impacting the survival of their species.
Periodical cicadas lack any true defense mechanisms, and are safe to handle. They do not sting or bite, nor are they toxic. If you happen to pick up a male, he may protest by emitting a loud buzz.
Range and Distribution:
Periodical cicadas are unique to eastern North America. The three 17-year species populate the northeast, primarily. Four 13-year cicadas live in the south and midwest regions.