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Anatomy Magicicada Roy Troutman

The excavation skills of cicadas

Cicadas spend most of their lives, as nymphs, underground. The large forelegs of cicada nymphs are adapted to digging through soil.

cicada foreleg
Image from The Periodical Cicada: An Account of Cicada Septendecim, Its Natural Enemies and the Means of Preventing Its Injury by C.L. Marlatt. 1898.

These videos demonstrate Magicicada nymphs digging through soil.

Magicicada nymph excavating tunnel by Roy

This magicicada nymph is excavating a make shift tunnel sandwiched between two pieces of plexiglass.:

Magicicada nymph emerging from burrow by Roy

Magicicada nymph emerging from burrow from Roy Troutman on Vimeo.

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Eye Color Magicicada Periodical Roy Troutman Video

White eyed magicicada by Roy Troutman

Here is a video of a rare white eyed magicicada. This is from a gene mutation that strepps the color from the cicadas eyes & also wings to some extent.

White eyed magicicada from Roy Troutman on Vimeo.

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Nymphs Roy Troutman Tibicen Video

Watch a Tibicen nymph emerge from the ground

This video by Roy Troutman shows a Tibicen cicada nymph emerge from the ground.

Annual cicada nymph emerging from burrow. from Roy Troutman.

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Anatomy Roy Troutman Tibicen Video

A Tibicen cicada breathing

Cicadas breathe through apertures along the side of their body called spiracles. This video of a Tibicen by Roy Troutman shows the opening and closing of a spiracle.

Adult Cicada breathing from Roy Troutman on Vimeo.

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Anatomy Audio, Sounds, Songs FAQs

What is the loudest cicada?

Africa is home to the Loudest cicada

A recent BBC article says researcher John Petti as found the answer: Brevisana brevis, an African cicada, reaches 106.7 decibels — with the loudest North American cicada, Megatibicen pronotalis walkeri at 105.9 decibels. Their sound was measured at a distance of 50cm (approximately 20 inches). Specifics about the equipment used and calibration of said equipment is not mentioned.

There are over 3500 types of cicadas in the world, and for now, Brevisana brevisis the king of the insect noisemakers. More information on Petti’s study can be found here. Sound files of Brevisiana brevis.

In North America

The article does introduce room for skepticism and debate, by noting that other species come very close (Diceroprocta apache), that the Megatibicen pronotalis walkeri alarm call reaches 108.9 decibels and a North American study that suggests decibels are correlated to body mass (and Brevisana brevis is not the most massive cicada).
Megatibicen pronotalis photo by Roy Troutman, taken in Batavia, Ohio
Megatibicen pronotalis photo by Roy Troutman, taken in Batavia, Ohio.

In Australia

According to the book Australian Cicadas by M.S. Moulds (New South Wales University Press, 1990) Cyclochila australasiae and Thopha saccata reach nearly 120db at close range. The “at close range” might be the key difference in measuring the sound, as Petti measured at a distance of 50cm.
Double Drummer (Thopha saccata)
Double Drummer (Thopha saccata), a cicada found in Australia, can reach 120db at close range. Photo by Kevin Lee.

What about Magicicada in the U.S.?

Personally, I’ve observed Magicicada cassini choruses achieve between 85 & 86 decibels (link to video), and M. cassini responding to fingersnaps (mimics female wing flicks) at as high as 116 decibels (link to video) 35s in). The 116 decibels level was recorded with the insect standing on the microphone of my Extech 407730. Magicicada choruses have been documented to reach 100 decibels

Magicicada chorus at around 80db:

Some people want to know how loud a cicada can get just because it is a cool fact to know, but others are concerned about noise-induced hearing loss (about which, I am not an expert). Both decibels and prolonged exposure seem to matter. According to the National Institute on Deafness and Other Communication Disorders page on Noise-Induced Hearing Loss, prolonged exposure to sounds over 85db can cause hearing loss (just above the chorus of a Magicicada). The WebMD harmful noise levels page has chainsaws and leaf blowers in the range of the loudest cicadas. Lessons learned: 1) Make sure you wear hearing protection if you plan on blowing leaves or searching for the loudest cicada, and 2) Do not complain about the cicadas in your yard — complain about your neighbors and their leaf blowers.

Male cicadas, in case you were wondering, use their opercula (flaps on their abdomen) to cover their tympana (the cicadas hearing organs) when they sing, so they don’t damage their own hearing. Cicadas — male and female — listen with their tympana.

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Megatibicen Neotibicen Paul Krombholz Teneral

It is possible to identify Tibicen just after they have molted

Paul Krombholz has come through with an awesome guide to identifying Tibicens just after they have molted. Click the image below for an even larger version. Note that the genus of these cicadas has changed to either Megatibicen or Neotibicen — notes below.

Paul Krombholz's image of recently molted and adult cicadas compared

Notes on the species from Paul:

N. pruinosus [formerly T. pruinosa]—Newly molted adult has darker mesonotum (top of mesothorax) than the very common T. chloromera. Abdomen is a golden orange color. Older adult has dark olive on lateral sides of mesonotum, lighter green below the “arches”.

M. pronotalis (formerly walkeri, marginalis)—Quite large. The reddish brown color can be seen on the mesonotum of newly molted adult. Older adult has solid green pronotum (top of prothorax) and red-brown markings on sides of mesonotum. Below the “arches” the mesonotum color can range from carmel to green. Head is black between the eyes.

N. tibicen [T. chloromerus, T. chloromera]—has large, swollen mesonotum, quite pale in a newly molted adult and almost entirely black in an older adult. Individuals from east coast can have large russet patches on sides of mesonotum. The white, lateral :”hip patches” on the anteriormost abdominal segment are always present, but the midline white area seen in my picture is sometimes absent.

N. davisi—Small. This is a variable species, but all have an oversized head that is strongly curved, giving it a ‘hammerhead’ appearance. Newly molted individuals are usually brown with blueish wing veins that will become brown, but some have more green in wing veins. Some may have pale mesonotums that will become mostly black. Older adults vary from brownish to olive to green markings on pronotum and mesonotum.

M. figuratus [formerly T. figurata]—a largish entirely brown cicada. Newly molted adult has a pink-brown coloration with some blueish hints. Older adult has chestnut-brown markings and no green anywhere. The Head is not very wide in relation to the rest of the body. The small cell at the base of the forewing is black.

M. auletes—a large, wide-bodied cicada. The newly molted adult is very green, but the older adult loses most of the green, usually retaining an olive posterior flange of the pronotum. The dorsal abdomen of the adult has a lot of powdery white on the anterior and posterior segments with a darker band in between.

From my own photos, here’s a sequence of photos of a Neotibicen tibicen tibicen as its colors develop.
Teneral Neotibicen tibicen

Here’s a comparison of two teneral Neotibicen linnei. Note the variation in colors — one green, one pink — from the same grove of trees in New Jersey. Color can vary a lot!
Linnei

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Neotibicen Teneral

A teneral female Tibicen tibicen tibicen

Earlier this week I was lucky enough to find a cicada nymph at a local park in Middletown, New Jersey. I took the cicada home, took some photos and then released it the next day. The cicada turned out to be a female Tibicen tibicen tibicen (formerly T. chloromera) aka a Swamp Cicada.

Female Neotibicen tibicen abdomen

Teneral Neotibicen tibicen

Teneral Neotibicen tibicen

Teneral Neotibicen tibicen

Categories
Anatomy Periodical

Cicada Myths

Cicada Myth Busters

There are many myths (widely held but false beliefs or ideas) about cicadas. Time to bust some cicada myths.

Myth 1: Cicadas are sleeping when they are underground.

There’s a popular meme that [mis]states the following “if cicadas can sleep for 17 years and then wake up only to scream and reproduce so can i”. The actual tweet doesn’t say “reproduce”, but I want to keep it clean.

American periodical cicadas aren’t sleeping the entire 17 years they’re underground. Much of the time they’re digging tunnels and building feeding cells, tapping into roots and feeding, vying with other cicadas for space along a crowded root system, growing (they experience four phases or instars while underground), avoiding unfavorable conditions like flooding, and possibly actively avoiding predators like moles and voles. Yes, cicadas can sleep — or at least the insect version of sleep called torpor — but they are definitely not asleep for 17 years.

That said cicadas do spend their time screaming (the males) and procreating once above ground.

Myth 2: All cicadas have a 17 year life cycle.

This is false. Only three species, out of the thousands of cicada species in the world, have a 17-year life cycle: Magicicada septendecim, Magicicada cassini, and Magicicada septendecula.

Myth 3: All cicadas have periodical life cycles and synchronized emergences.

This is false. Only seven species in the United States (belonging to the genus Magicicada), and a few species in Asia (belonging to the genus Chremistica 1) have been confirmed to have periodical life cycles and synchronized emergences.

All other species of cicadas emerge annually, although in some years they are more plentiful than in others.

Myth 4: All cicadas live a prime number of years.

Many cicadas live a prime number of years, but some do not. Chremistica ribhoi, the World Cup cicada, has four year life cycle.

Myth 5: A long, periodical, prime number life cycle has allowed American periodical cicadas to avoid gaining a predator.

American periodical cicadas have avoided gaining an animal predator that specifically predates them, but they haven’t avoided a fungus. Massospora cicadina is a fungal parasite of Magicicada cicadas.

Male Magicicada septendecim infected with Massospora cicadina fungus

That said, just about any animal will eat an American periodical cicada, so they definitely get eaten. They get eaten a lot.

Myth 6: Cicadas make their well-known sound by stridulation, like crickets, grasshoppers & katydids.

It is true that some cicadas can make noise by stridulation, making sound by rubbing body parts.

However, and this is a huge “however”, the sound cicadas are known for is made by organs found in male cicadas called tymbals. Tymbals are a pair of ribbed membranes, that produce the cicada’s sound when they are flexed in and out by muscles. The mechanism is like the popping sound made when the plastic of a soda pop bottle is flexed in and out.

Tymbal

Cicadas can also make sound by flicking or clapping their wings.

Myth 7: Cicadas eat vegetation.

This is false. Cicadas lack the mouthparts to chew and swallow vegetable matter. Your tomatoes are safe around cicadas. Rather than eating solid food, cicadas ingest xylem, which is a type of tree sap that cicadas drink through their straw-like mouthparts.

Myth 8: American periodical cicadas are locusts.

Cicadas are not locusts. Locusts are a form of grasshopper. People confuse cicadas with locusts because both insects aggregate in massive numbers.

This is an image of a locust:
Locust

Characteristic Locust Cicada
Order Orthoptera Hemiptera
Hind Legs Giant hind legs for jumping Hind legs about the same size as other legs; great for climbing and perching.
What they eat Everything green they can find to eat Xylem sap
They’re in your town All the plants in your town have been stripped bare Cool UFO movie soundtrack sounds during the day

9) If you see a W appear in a cicada’s wings it means there will be a war. If you see a P, there will be peace.

This is the most mythical of cicada myths and has no basis in fact. That said, here’s the W:

W in cicada wing

1 Hajong, S.R. 2013. Mass emergence of a cicada (homoptera: cicadidae) and its capture methods and consumption by villagers in the ri-bhoi district of Meghalaya. Department of Zoology, North-Eastern Hill University, Shillong — 793 022, Meghalaya, India.

Categories
Anatomy Dundubia Santisuk Vibul Thailand

Cicada anatomy photo by Santisuk Vibul. Dundubia sp.

This photo points out the Tymbal (the organ that makes the cicada’s signature sound), the Tympanum (their hearing organ), the Operculum (which covers the Tympanum), and its wings.

Dundubia

Dundubia

Dundubia

Dundubia

Categories
Anatomy Audio, Sounds, Songs Australia Cyclochila Video

A third way cicadas make sounds

Cicadas are well known for the songs male cicadas make with their their tymbals, which are drum-like organs found in their abdomens.

Some female cicadas will also flick their wings to get the males attention. Watch this video where a male Magicicada is convinced that the snapping of fingers is a wing flick. Note: Magicicada males will also flick their wings once they become infected with the Massospora cicadina fungus (which removes their sex organs).

There is a third way some cicadas can make sounds. This method of creating a sound is unique to the Australian species Cyclochila australasiae (aka the Green Grocer and Masked Devil). These cicadas have stridulatory ridges on their pronotal collars (the collar shaped structure at the back of their head), and a stridulatory scraper on their fore wing.

From M. S. MOULDS, 2012, A review of the genera of Australian cicadas (Hemiptera: Cicadoidea). Magnolia Press Auckland, New Zealand. p84:

Cyclochila is unique among the Cicadoidea in possessing a stridulatory file on the underside of the lateral angles of the pronotal collar that interacts with a scraper on the fore wing base (Fig. 132). Rubbed together these produce low audible sound in hand-held specimens (K. Hill, pers. comm.), the purpose of which is for sexual com- munication at close quarters (J. Kentwell and B. Fryz, pers. comm.)

Here is a photo of these structures:

Structure on Green Grocer

The location of these structures is right about where the blue pin is in this photo:
Collar

Update:

Tim McNary of the Bibliography of the Cicadoidea website, let us know that Clidophleps cicadas are also able to create should using a stridulatory structure. Clidophleps is a genus of cicada that can be found in California, Nevada, Arizona, and I assume adjacent parts of Mexico. Clidophleps differs from Cyclochila in that the stridulatory structure is on its mesonotum, and not its pronotal collar.

Photo courtesy of Tim McNary:
stridatory file