Entomologists: How do I preserve dead insects?

Earlier this morning, we found a very large and cool-looking beetle in our pool skimmer. It appeared to be dead, but perfectly in intact, so I held on to it (much to my mom’s and sister’s horror) in the hopes of identifying and keeping it in some kind of little display or something. It’s a very pretty June Beetle, so my guide tells me. I’ve never seen any around here before.

So, I ask anyone into entomology–professional or amateur–is there anything special to do to preserve and display insects like this? I mean, I’ve seen little bug carcasses elsewhere in little nooks and crannies of the house, and they don’t seem to do anything but collect dust, but I just want to make sure. What’s the best way to keep them? In a kind of cotton-lined box with a glass top, like I see in various museums and other collections?
Granted, though, as of the time of this writing, I can’t apply any preservation/display advice for the June Beetle… I just opened up the little holding box he’s in and he appears to be moving somewhat. I suppose I could finish him off with some soapy water or something, but then I’d feel bad for killing it. I’ll probably just hold on to him until he’s fully up and running, then release him back outside, saving your tips for the next opportunity that comes my way. Unless June Beetles are considered plant-devouring pests, in which case I’ll have no qualms about killing yet another critter that’s trying to eat our house and everything else in and around it…

But yeah. Preservation and display. What say you?

I don’t know about bugs specifically, but human and animal tissue is best preserved in a fixative such a formalin (basically a 10% buffered solution of formaldehyde). I don’t see why this also wouldn’t work with insects. I also don’t know how available this stuff is. Maybe if you ask nicely at your local lab? If you do manage to get some, don’t flush it down the drain if you decide to get rid it.

On second thought, putting the bug in a container full of absolute alcohol (100% ethanol) might be easier for your purposes. Isn’t Everclear nearly 100% alcohol? I think that might work.

Er, I don’t believe bugs are usually preserved in alcohol or formalin.

IIRC, (I used to collect them when I was a kid, but it’s been a while) you preserve most insects by pinning them into the position that you want to display them in while they’re still moist, and then letting them dry out.

Yup. Kill it, stick a pin in it, and let it dry out; details here.

The killing part is important. As a little kid, I collected a jar of bugs, and left them out all night. In the morning they appeared to have died, so I put pins through and attached them to a board. Several hours later, I was horrified to discover the insects writhing about; grasshoppers kicking their legs and hopping off with pins still through their middles. :eek:

Interesting. Don’t they start to rot after a while? If not, why not?

Well, insects got that name because of their body shape. The word comes from Latin insectus, literally meaning ‘cut in’. In means in, same as in English, and sectus means something that got cut or divided, from secare, to cut (think of a “secant” cutting across a circle, or the word “section” from the same origin). Because insect bodies are divided into 3 sections: head, thorax, and abdomen…

What’s that?

(psst psst psst)

Oh! Never mind…

Chitin, which forms the insects exoskeleton, is not very prone to rot, and under normal conditions of humidity the very small amount of muscle and other tissue inside dries out so thoroughly that molds etc usually can’t take hold. If they do, they will rot through the thinner parts of the exoskeleton first, and the specimens will fall apart. However, this is usually not a problem except in areas with high temperatures and humidity. In Florida or the tropics an insect collection may need to be treated somehow.

Another possible problem is that tiny dermestid beetles can become established in a collection and chew the specimens apart.

If the specimens are valuable, or are going to be stored away for some time, one preventive is to pin a moth ball in one of the corners of the case to keep dermestids from taking over.

Here’s another useful link :http://www.extension.umn.edu/distribution/youthdevelopment/DA6892.html

For the odd record: My family once left our pet tarantula with one of my Dad’s fellow biologists in NY while we were on a fieldwork trip to Mexico. When we came back, he had "pinned"our pet, claiming it had died. In questioning, my Dad didn’t buy it, it was a rare species. All six kids were crying about our pet, and it was an awful rift between he and his fellow biologist after that.

I have some sad issues with pinning. Anyone know of a good therapist dealing with children raised by biologists???

Sorry for your loss. :frowning:

You’re not supposed to pin spiders, anyway. The exoskeleton is thin, and they tend to just shrivel up. I guess you can get away with it with something as big as a tarantula.

Would Formalin or alcohol help preserve spiders? Well, maybe not spiders, that might dry them out too much.

Can you tell I’m just aching to dunk some bugs in noxious chemicals? :slight_smile: Too bad we don’t have any here. Except mosquitoes. Damn them all to hell.

Spiders are usually preserved in

70% alcohol
(ethanol or isopropyl). Insects can also be preserved this way, though dried ones are more convenient for study and storage.

Coding fixed:

Spiders are usually preserved in 70% alcohol (ethanol or isopropyl). Insects can also be preserved this way, though dried ones are more convenient for study and storage.

Thanks for that, Colibri. I dunno, my Dad, who is astute with insects, was so pissed about the whole thing: it was a rift… with the other professor living two doors down.

Still, have to look back, and see the rift of two families circa 1973: “Ya killed my tarantula, ya bastard” …

Sounds like an Addams family plot line.

I once took an entomology course, which required submitting an insect collection.

We were required to use glass jars (a baby food jar works well), with the insect preserved in Methyl Hydrate. (It’s a liquid - you can buy it at the hardware store.)