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Word Games

A recent posting of 2 skins here was titled "Damselfly and Dragonfly Exuviae". Another image of a single skin here was titled "Damsefly Exuvia".
When a larval insect sheds its exoskeleton (=skin) the cast-off exoskeleton is singular. However if one uses the term exuviae for this cast-off exoskeleton the word is plural. In the entomological sense a cast-off exoskeleton consists of several insect parts (head, thorax, abdomen, etc.) and thus the word is exuviae. If one was just describing a single leg I suppose that this could be an exuvia. However, a single cast skin is a collection of insect parts and is thus an exuviae.

More on exuvia
According to Massachusetts Cicada: "Exuvia is the plural of Exuvium and are cast off skins that are left behind during a molt process. Specifically during a Cicada's 5th instar stage, it is the brown husk that is usually left behind on trees and bushes."
Their words, not mine.

That site I think is definitely wrong. I don't think there is such a word as "exuvium", and "exuvia" is the singular of "exuviae" (but apparently not used in the singular form by most authorities).

Tis a puzzlement...
Apparently this topic has been discussed before. In fact, the item I linked to cites an old article on the subject!

Here's my take on it, after checking the Perseus Digital Library Tools:

Classical Latin has two similar words derived from the verb exuo- "to draw out or off, to pull or strip off, put off, divest": exuvium/ plural exuvia- "spoils, booty", and exuviae (always plural)- "that which is stripped, drawn or taken off from the body, clothing, equipments, arms, etc." Exuviae is specifically mentioned as being used to refer to an animal's skin.

Exuvium is only mentioned in one of the online dictionaries, with one reference, while exuviae is mentioned in both, with numerous references. From this I would infer that exuvium is not used much in classical Latin.

Of course, scientific Latin is a descendant of classical Latin, not classical Latin itself, so it's possible that usage has changed. Still, I suspect that exuviae is to be preferred.

It looks like it boils down to two choices:

Exuvium and its plural exuvia (very little support in classical Latin)

Exuviae (amply supported in classical Latin and supported/ insisted on in at least some areas of scientific Latin usage.

Either way, exuvia as a singular is wrong (it isn't even mentioned in the classical Latin dictionaries). It seems to be what etymologists call a back-formation, like pea (derived in Middle English from singular pease and plural peasen) or specie (based on the mistaken impression that Latin plurals work like English).

It strikes me odd
that they use the word "exuviae" in their URL! Each to his own, so let the Cicada people use Exuvium and the rest of us can go on using Exuviae.

Exuvia, Exuvium and Exuviae
Hey all,

Sorry to bring this topic back to light after a month but I just stumbled upon this posting.

With regards to my url being I too thought that it was the plural of "exuvum" but I was corrected on my use of the term by Chris Simon, Professor; Editor of Systematic Biology, University of Connecticut at Storrs who set me straight as to how to properly use these terms. As I too had noticed these differernt terms back in 2004.

My question to her:

Hi Chris,
Thanks for getting back. I actually managed to figure out the term for teneral. I did however think that exuvum was spelled right, are you saying that a single cast-off shell is "exuvium"? If it is wrong then I feel like a real dork :)

Her response was as follows:

Hi Gerry,
A single cast off shell is an exuvium. Two are exuvia.

Since the page was already named "exuviae.asp" I decided to keep it named that way because it was already indexed by the search engines and by changing the name of the page would cause a 404 "page not found" if anyone clicked on it so I left it alone.

Now who is right or who is wrong? Well, I look at it this way, since Professor Simon has a 20 year head start on me in terms of knowledge of cicadas and insects in general, who am I to argue? :)

Thanks for reading.
Gerry Bunker
Massachusetts Cicadas

So it's like a pair of pants you take off?

Thanks, Tony -- I'll fix those postings and my "Dragonfly exuvia".

Is this a universal convention among entomologists? I tried googling the terms before I posted those specimens and quite a few sites used the singular form, e.g. and

Hi Peter
Obviously not universal. I took my last formal entomology university course about 40 years ago. Perhaps things have changed since then. In those days, our morphology bible was R.E. Snodgrass "Principles of Insect Morphology". He defined Exuviae as "The cuticular parts discarded at a moult". Note he says "parts" (plural) at a moult (singular) He makes no mention of Exuvia.
Glad I called it word games.

What's a pair of exuviae?
How best to describe "Damselfly and Dragonfly Exuviae"? (;-)

Same as pants
Boys pants, girls pants, boys and girls pants.
Checked Needham et al. 2000. Dragonflies of North America. They define exuviae as "shed larval cuticle left behind after a molt, especially after transformation to the adult stage; always plural"

"always plural"
says it

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