How To Determine Gender of Nymph Skins

How To Determine Gender of Nymph Skins

Have a look at the picture to the left. See that brown thing? That is a cast off nymphal skin (exuvium) of a Tibicen lyricen cicada. Pretty cool huh? Ever wonder what the sex of something like that is? Well, just recently I learned the trick to determine which gender of cicada left the nymphal skin behind, a girl cicada or a boy cicada.

To be honest, I could never figure it out until recently. And in the spirit of what this web site is about and I quote:

I'm going to try to learn something and to let others know what I learn by taking careful field notes and documenting everything that I see as it pertains to Cicadas in Massachusetts. Who knows? Maybe we can learn something together.

Determining Boy Cicadas

A cicada exuvium's abdomen is divided into sections or sternites. There are 9 total sternites on cicada nymph skins. At the very tip (9th sternite) you can make out a "bulbous" structure. This nymph skin contained a male cicada.

Determining Girl Cicadas

Girl cicadas also have this "bulbous" structure at the 9th sternite. But unlike males, females have two cylindrical-type structures at the 8th sternite. These structures are also known as "processes". Between you and me I'd tell you what they REALLY look like but this is a family site. Compare the two, I'm sure you can clearly see the difference now.

Special Note: Thanks to Roy Troutman for the use of his images and for taking the time to share this with me. Visit Roy Troutman's Cicadas on Cicadamania.