Cicadas are winged insects with a loud buzzing sound that can be heard all summer. They live on every continent, except Antarctica. Each year, cicadas are seen from late June to August. The only known species of periodic cicadas is found in North America. They appear from late April to early May and last for 13 to 17 years depending on their species.
What do cicadas look like?
According to Scientific American, there are approximately 3,400 species of cicadas. Seven are periodic cicadas. There are three 17-year-old cicada and four 13 year cicada species. According to Cicada Mania, all cicadas have bulging eyes. These eyes are black in annual cicadas and bright red in periodic cicadas. However, in rare cases, periodical eyes can be blue, yellow or multicolored.
According to North Carolina State University, Raleigh, annual cicadas can have solid or patterned bodies that are approximately 1.75 inches (44 mm) long. The bodies of periodic cicadas are deeper black than annual cicadas and measure between 0.75 and 1.25 inches (19 to32 mm). Cicadas have transparent wings with veins. In some species, darker veins at the tips of their wings make a "W". They don't have stingers and no chewing mouthparts so they can't bite. The ovipositor is a sharp organ that allows females to lay eggs. Males have ribbed Tymbals, which are exoskeleton structures consisting of flexible and rigid membranes on their first abdominal segment. The distinctive summer song of the Cicada is produced when males quickly expand and contract their Tymbals.
Cicada Taxonomy Kingdom: Animalia Phylum: Arthropoda Class: Insecta Order: Hemiptera Family: Cicadidae Source: ITIS
Cicadas, also known as nymphs or juveniles, are white and resemble termites or ants when they are young. They molt underground through several instar stages, which are nymph stage nymphs. The last instar stage is when nymphs emerge out of their burrows. The nymph stage aboveground is wingless and has a light-brown exoskeleton. It also has large front limbs which it uses to attach itself to tall grasses or trees in preparation for its final molt.
According to the University of Connecticut (UConn), in Stamford, adults are soft and pale when they break free from the nymphexoskeleton. However, their bodies become hardened and darker over the next few hours. Their exoskeletons take approximately four to six days to fully harden.
How do cicadas reproduce?
The loud buzzing sound that cicadas make is a mating call. Male cicadas sing in choruses using their tymbals to vibrate. This song attracts males as well as females who cluster together to mate. The males eventually die, and the females start to lay 20 eggs at a time. They insert their ovipositors into the slits of tree branches.
Within six to ten weeks, the eggs hatch and the nymphs burrow into soil to absorb nutrients from the plant roots.
An annual cicada leaps from its Nymph Exoskeleton in Klaten (Indonesia) every year. (Image credit: Sriyana Sriyana/EyeEm/Getty Images)
What are the habits of cicadas?
According to the Museum of Zoology at the University of Michigan, Cicadas spend their entire lives underground as Nymphs. Then, they reach adulthood in a period of two to six weeks, usually in trees close to where they emerged.
According to Texas A&M University, College Station, the subterranean stage for annual cicadas lasts between two and five years. For periodic cicadas, however, the nymphs will not see sunlight for 13 to 17 years. The nymphs of periodic cicadas emerge when soil temperatures reach 64 degrees Fahrenheit (18 degree Celsius) and the depth is 12 to 18 inches (31-36 centimeters).
Common cicada (Tibicen linnei) on a branch in Toronto, Canada. (Image credit: Photo by Creative Touch Imaging Ltd./NurPhoto via Getty Images).
Periodical cicadas are a group of nymphs that appear in the same place at the same time. This can happen for a few weeks or more. As many as 1.5 million insects could cluster on one acre. Broods are a group of periodic cicadas that appear on the same cycle. Each brood is classified using Roman numerals. There were 30 known broods in the northeastern United States at one time. Scientists have been able to consolidate some broods over the years, while others have disappeared due to habitat fragmentation or human development. UConn reports that there are currently 12 active broods consisting of 13-year-old cicadas and three broods.
Brood X also known as The Great Eastern Brood is the most widespread of periodic cicada broods. It has been seen in 15 states, including New York and Illinois, as well as as as far north as Michigan, and as far south to Georgia. According to Cicada Mania, their last appearance was in 2021 and they will not be seen again until 2038.
What do cicadas eat?
According to the Missouri Department of Conservation, Cicadas are true bugs in the Hempitera order. They have sucking mouthparts that look like straws and can be used for sucking up liquids inside plants. According to UConn, Nymphs eat fluids from roots while adults eat fluid from branches.
Although cicadas can sometimes be mistakenly called "locusts", they are not part of grasshopper orders. Cicadas don't eat grasshoppers, according to the Ohio State University College of Food, Agricultural and Environmental Sciences. OSU states that female cicadas can cause damage to young trees when they lay eggs using their sharp ovipositors. This can prevent the trees from bearing fruit.
Are cicadas endangered?
According to the International Union for Conservation of Nature, although no species of Cicada are endangered, there are a few that could be at risk. According to IUCN, the Red List of Threatened Species of the organization lists the periodic cicadas Magicicada caussini and Magicicada septendecim as low risk/near threatened because their habitats are extremely fragmented and there is a decline in mature individuals over the past decades.
Other cicada facts
Nature says that male cicadas' choruses can be as loud as a jackhammer at 80 to 100 decibels.
Scientific American claims that Cicada wings are waterproof, antimicrobial, and resistant to bacterial growth.
According to Cicada Mania, cicada nymphs will sometimes construct chimneys or turrets out of mud when they leave their burrows.
You can listen to different songs from Cicada species on the website Songs of Insects - A Guide to the Voices of Crickets and Katydids - or you can download them all.
Additional resources
This article was written originally by Alina Bradford, a Live Science contributor. It has been updated since then.
