Finally getting around to spreading some Acronicta specimens I collected in Arizona this past August at the Southwestern Research Station. Time flies when you have tons of busy-work and no time to focus on your own research ideas. Ha!
For those who don’t know, spreading moths and butterflies is tricky business. It takes a lot of skill and practice, and your success depends on several factors: how shaky your hands are (one of my friends drinks a ton of coffee and then complains about how difficult it is to pin her insects), how fresh the material is, the size of the specimen, and how strong the wing muscles are. Learning good technique from an expert is recommended (my advisor is one of the best!).
Freshly killed specimens are the easiest to work with, especially when you are dealing with micro moths – they can dry out in a manner of minutes. Thankfully my moths are measured on the order of a few cm instead of a few mm. If you have to let your specimens dry out first you can leave them in an envelope in a freezer, or you can field pin them, like in the photo above. Just leave them in their normal resting position. Then if you want to spread them, you need to create a relaxing chamber. I accomplish this with a series of tupperware containers and paper towels soaked with water. A tightly sealed lid keeps in the moisture.
The length of time varies, you want to wait until the insects are pliable again. If you are too anxious and take them out early, you will be snapping off wings and legs. If you wait too long, the specimens will start growing mold. I usually wait a day or two, and test them by gently nudging the antennae. When the antennae are soft, they are probably ready to go.
I think I’ll take some in-progress photos as I pin these to share some of my techniques. I have been pinning leps since I was about 10, and it is one of my favorite mind-numbing activities.