Cicada Basics

Cicadas belong to the insect Order Hemiptera, which also includes aphids, scale insects, plant bugs, stink bugs, and relatives.  More specifically, cicadas (Family Cicadidae) are related to treehoppers and leafhoppers.  There are approximately 170 species of cicadas known from the US and Canada, but Wisconsin is home to only a fraction of these.

Wisconsin is home to two main types of cicadas—our “annual” cicadas, which are seen every year, and our “periodical cicadas” (Magicicada spp.). These cicadas all have the same general body shape and similarities in their life cycles, but they differ subtly in their appearance, biology, songs, and distribution in Wisconsin.

Explore the expandable panels below to gain a basic understanding of cicadas and their biology.  Below that, learn about Wisconsin’s main types of cicadas.

This is an accordion element with a series of buttons that open and close related content panels.

General Appearance

As far as Wisconsin’s insects go, adult cicadas are relatively large—often 1+ inches in length, with thick, robust bodies.  The four membranous wings possess many veins and closed “cells”; the wings extend beyond the end of the abdomen and are held roof-like over the body at rest.  The head is robust with prominent eyes and a bulging, “radiator-like” structure (clypeus) on the front of the “face”.  The antennae are short and bristle-like and the elongated, tubular mouthparts project backwards along the underside of the body.  The six legs are relatively slender and jut out from the underside of the body.

Comparison of a dog-day and periodical cicadas
[Left] Side view of a northern dog-day cicada. Photo credit: Ryan Hodnett via Wikipedia, used by CC 4.0. [Right] Front of a periodical cicada showing the structure of the head, including antennae and mouthparts. Photo credit: Anders Croft, USDA Bee Inventory and Monitoring Lab via Wikipedia, public domain image.
Upon emergence from the soil, cicada nymphs (juveniles) can also be recognized by their relatively large size.  Nymphs are generally brownish, with an arched body and a somewhat crayfish-like appearance.  Similar to the adults, they also possess a bulging, “radiator-like” structure (clypeus) on the front of the head and tubular mouthparts that project backwards along the underside of the body.  A key feature of the nymphs is the widened, “fossorial” forelegs, which are adapted for digging in the soil.  Nymphs lack wings, but there are often noticeable “pads” or “buds” resembling wings.

Shed cicada exoskeletons
Cicada exuviae (shed exoskeletons) serving as a reminder of what the nymphs looked like. Photo credit: Martin LaBar via Flickr, used by CC 2.0 DEED.    

Basic Life Cycles

Cicadas undergo “incomplete” or “gradual” metamorphosis (technically, they’re paurometabolous) and all cicadas start out as eggs.  After mating, adult females cut small slits into plant material (e.g., twigs) to deposit their eggs.  In many cases, females can deposit several hundred eggs in small batches during their short period of activity.  The eggs hatch, often after several weeks, and the very small nymphs drop to the soil where they spend the majority of their lives.  The exact life span varies for each species of cicadas, but often takes several years all the way up to 13 or 17 years for the periodical cicadas.  The nymphs reside in the soil, often at a depth of 8-12 inches and use their sucking-type mouthparts to drink sap from trees.  This fuels their growth and development, and plants seem to tolerate this feeding activity without issue.  After passing the appropriate amount of time below-ground, cicada nymphs tunnel upwards and emerge through holes in the ground.  In some cases, they may construct small turrets of soil near their emergence holes.

Cicada emergence holes in ground
Cicada emergence holes in the ground. Photo Credit: US Department of Agriculture via Flickr used by CC by 2.0 DEED.

After emerging above-ground the nymphs typically climb onto a vertical surface to molt and transform to the adult stage.  As the new adult emerges from the old exoskeleton, the cicadas are particularly vulnerable as their bodies have not yet hardened.  These newly-emerged (teneral) adults are pale, but darken and harden after a short period of time.  Individual adults are not very long-lived, so they quickly get to mating and laying eggs.  The exuviae (old exoskeletons) remain behind as evidence of their recent molt.  Adults are short lived and often only live for several weeks.

Animation of a molting cicada
Animation of a molting cicada. Photo credit: T. Nathan Mundhenk via Wikipedia, used by CC 3.0.
Mating cicadas
A mating pair of periodical cicadas. Photo credit: G. Edward Johnson via Wikipedia. Used under Creative Commons 4.0 License.


With their short adult lives, cicadas don’t waste much time trying to find mates.  To that end, adult male cicadas produce sound (i.e., “sing”) to attract females.  The exact frequency and pattern of the singing can vary for each type of cicada.

To produce this sound, males possess drum-like membranes (tymbals) on the sides of their abdomens. Rapid muscle contractions cause the shape of the tymbals to change, which produces sound. Male abdomens are mostly hollow, and the resulting air space further plays a role in producing sound.  These calls can be quite noisy and may create a chorus-like effect in wooded areas. Large groups of periodical cicadas can produce sound in the ballpark of 80+ decibels (similar to an alarm clock), and sound levels very close to calling cicadas could be close to 100 db (similar to a motorcycle or snowmobile). For a deeper dive into sound production by cicadas, the article How Cicadas Make Their Noise in Scientific American is an excellent read.

Sound-producing structures of cicadas
Illustration from Marlatt’s 1907 report showing the tymbals and associated muscles for producing sound. Source: Marlatt, C.L. 1907. The Periodical Cicada, USDA Bureau of Entomology Bulletin No. 71.

While males may be making all the racket, receptive females can respond as well.  At close range, periodical cicada females can flick their wings to produce a brief snapping noise, which can lead to a back-and-forth between males and females before mating.

The famous naturalist, Sir David Attenborough, even mimics this on film with amusing results!

Common Types of Cicadas in Wisconsin:

Dog-Day Cicadas:

Our commonest cicadas in Wisconsin are known as or “dog-day” cicadas (Neotibicen spp.) as they appear during the hot “dog days” of summer.  These and other cicada species that emerge every year are referred to as “annual” cicadas.

Appearance: These cicadas are large (1 ¼ – 1 ½ inch long), with a dark black and greenish color; their wings have green veins. The underside of the body is grayish and the eyes are dark.

Life cycle: Despite having life cycles typically ranging from 2-5 years, there are overlapping generations and these insects can be spotted every year in the Midwest.

When & where: Our dog-day cicadas are common and widely distributed in the Upper Midwest.  They are typically spotted during the hot summer days of July, August, and September.

How many: While these cicadas can be common, they generally emerge in relatively small numbers compared to the periodical cicadas.  Finding 10-20 in a yard isn’t unheard of, but you won’t encounter thousands as with periodical cicadas.

Song: Our dog-day cicadas have a song reminiscent of an electric buzz-saw, with a high-pitched buzz lasting roughly 15 seconds.


Adult dog-day cicada
A dog-day cicada from a residential backyard setting. Photo credit: PJ Liesch, UW Insect Diagnostic Lab.

Periodical Cicadas:

Appearance: Adult periodical cicadas are black with orange on the wings and legs; the eyes are distinctly reddish. There’s also a bold “W” pattern towards the tips of the wings. Periodical cicadas tend to be slightly smaller in size than the dog day cicadas.

Life cycle: Our periodical cicadas in Wisconsin (Brood XIII) have extended 17-year life cycles.  After emerging from the egg stage, juvenile (nymphs) burrow into the ground where they complete most of their life cycle, only emerging as adults 17 years later.

When & where: Periodical cicadas have historically been documented across a swath of counties in southern Wisconsin.  While this gives the impression of them being widely distributed, they actually occur in isolated pockets in southern Wisconsin.  See the “When & Where” page for more details about distribution.  Compared to our dog-day cicadas, periodical cicadas emerge much earlier in the state and are typically active in late May and into June.  By July, activity subsides.

How many: Periodical cicadas can emerge in tremendous numbers.  In areas with high periodical cicada populations, densities can often be on the order of tens or hundreds of thousands per acre—sometimes even more!

Song: The song of each periodical cicada species can differ, but a chorus of our common species in Wisconsin (Magicicada septendecim) sounds like a group of frogs with occasional “weee-oh” syllables, giving impressions of a “sci-fi” or “UFO” sound effect.  Individual males sound as if they’re saying “wee-od” or “fayyy-roh” (as heard during the intro of this video).

Adult periodical cicada
Adult periodical cicada Magicicada septendecim. Photo credit: JanetandPhil Gallagher via Flickr, used by CC by 2.0 DEED.