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Cicada Molting/Eclosing Process

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Cicada Molting/Eclosing Process

Cicada molt/eclose process

The Cicada molt process is a long and lengthy one. Below is a detailed account of a Tibicen lyricen molt from start to finish. This was the first nymph I discovered for the 2004 season so I was keen on noticing every single detail.

  • 10:45pm - After some initial movement to find the perfect spot, the nymph has finally settled down. I could hear "scratching" sounds as the Cicada flexed it's legs in order to get a firm grip on the branch.
  • 11:09pm - A split appears starting between the compound eyes to the end of the thorax.
  • 11:14pm - The split grows wider.
  • 11:19pm - The split grows even wider, the cicada teneral struggles to remove it's head from the exuvum.
  • 11:24pm - The head is finally free. I noticed that the Cicada teneral is trying to wriggle free by rapidly "vibrating" it's upper half.
  • 11:30pm - After more vibrations, the wing buds are free. The front forelegs were free'd immediately after snapping this picture. The Cicada teneral hangs up-side-down. It's moving it's forelegs slightly. I notice 2 "string-like" structures. I need to figure out what the heck those are for. I wonder if hanging in this position helps blood to flow with the use of gravity? I'm not quite sure if it can see immediately with those big compound eyes.
  • 11:37pm - Still up-side-down. Seems to be a female. It's still doing the vibrating body thing while up-side-down.
  • 11:50pm - Still up-side-down.
  • 11:52pm - The cicada teneral does what amounts to a "sit up" and grasps the exuvum with it's front forelegs and pulls its abdomen out. It hangs onto it's exuvum with it's fore and mid legs. It flexes it's wing buds to perhaps get blood flowing through the green wing veins. It's moving it's wings a lot.
  • 11:56pm - The wings are starting to look more like wings now. I noticed that the lower sternites and tergites of this female seem to be swollen.
  • 12:09am - The wings are still growing.
  • 12:14am - When the wings fully expand, they start out parallel to the body.
  • 12:14am - Another view of the wings parallel to the body. The cicada teneral is hanging onto it's exuvum with just the front forelegs. Sex organs are clearly visible. Wings are pulsating slightly. Can make out ovipositor.
  • 12:20am - The wings eventually fold in forming a "roof-like" structure over the Cicada's abdomen. Can make out four wings total, two on each side. After an additional hour the wings and cicada will harden. The wing veins will turn blackish brown.
  • 12:25am - The Cicada teneral profile is shaped like a "bullet" with wings. Extremely aerodynamic but are noted to be real clumsy fliers.

"Cicada Molt Process - Why Does it Take so Long?"

Believe it or not there is a method to all the madness when Cicadas molt. I have a theory on why it takes so long for a Cicada to complete it's molt process.

You see, a Cicada, like all insects do not have a closed circulatory system like you and me. Their circulatory system is open, which means that blood flows freely around the body saturating the organs while supplying them with nutrients. This free flowing of blood helps the Cicada to harden. Which is why over time, the Cicada get's darker and darker in color. However, not much blood flows to a Cicada's legs as they remain mostly hollow. This is why a Cicada stays so long in its upsidedown position. Since their legs start out soft, if they try to use them to support their weight too early that would probably be disasterous.

"The Soft and Chewy Cicada Teneral Stage, Yumm!!"

The teneral stage is that stage in a Cicada's development where the Cicada has just finished carrying out it's molting process but it is still relatively soft. Like the consistancy of a newly molted soft-shelled crab. Hey, they are arthropods after all. It is mainly pinkish in color with either light blue or light green colored wing veins. It's at this stage where the Cicada is most vulnerable. Typically not much happens during this stage because most of its efforts are focused on hardening to its darker more earth-like colors.

Usually the Cicada teneral will not leave the vicinity of it's discarded nymph shell (exuvum) but it has been noted on some occasions that the Cicada will often move a fair distance away from its nymph shell to find a more secluded spot to harden. The wings are very fragile at this stage, should they brush up against something or be touched by human hands, irreparable damage can be done to the wings.

But, its during this stage that you can actually eat Cicada Tenerals. That's right, if you like lobsters or other shell-fish then Cicada Tenerals may be just what you are seeking. Don't make that face! After all it's all protein right? Do a search on Google for "cicada teneral recipes", and you'll see what I mean.

"Cicada Pee - When you Gotta Go, You Gotta Go!"

Cicada Pee.I have noticed on several occasions that a Cicada teneral will sometimes urinate after the molt process. Why the Cicada does this is unclear. Perhaps it has something to do with their long development below ground where a Cicada nymph feeds on the xylem of their host plant and expells this in the form of a waste product once they have emerged from the ground. Click the thumbnail to the left for a closer look.

Date Posted: 2010-06-02 Comments: (4) Show CommentsHide Comments

Comments

Posted By: Brewer's | On: 2012-07-24 | Website:

We have a molting Cicada on our fencepost this evening and are in true amazement! We followed it's journey along with your pictures and couldn't wait for the next stage! Thank you for such a wonderfully detailed account of this incredible process!

Posted By: Massachusetts Cicadas | On: 2012-07-24 | Website:

Hi There,

Glad you were able to witness this amazing feat of nature. Consider yourself lucky as most people just find the cast-off nymph skin.



If you're so inclined maybe you can send in a few photos by filling out the report a cicada or cicada killer report form here. We will show the cicada in our sightings section and you will be adding useful distribution data to our database. The form can be found at the below link. Simply copy and paste it into your browser's address bar.

http://www.masscic.org/report_cicadas.php

Posted By: christina | On: 2013-08-30 | Website:

my husband found a cicada that looked like it was getting ready to molt, but it was on the ground so I put it in a container. I left it in there overnight and checked on it the next morning but it still had not molted. the hardened shell started to split on the back but the cicada still has not come out. it appears to still be moving inside, do you think there is something wrong with it because every website I've looked at says they should molt within 2 hours? thank you for your time and your feedback.

Posted By: Massachusetts Cicadas | On: 2013-08-30 | Website:

Hello Christina,

Thanks for the comment. Unfortunately, if the cicada was in the process of molting and all of a sudden has stopped, that usually means it will not molt. There could be a myriad number of reasons why this may happen. Even when molting completely, injuries can occur causing injuries that ultimately result in death.

I wrote another article entitled "When Ecdysis in Cicadas Goes Wrong" which discusses these fatal injuries. http://www.masscic.org/cicadas101/when-ecdysis-in-cicadas-goes-wrong

Now I fear that the cicada is alive but its stuck. Since it won't be able to feed it will starve to death then die. That is nature I suppose. Thanks for sharing your story.

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