Name this bug, please!

September 22, 2009 5:29 PM

I can't seem to identify these bugs. Help!

At first, I panicked when these swarmed next to our house today because I immediately assumed that they were termites. But they definitely have ant-shaped bodies (with a defined waist), unlike a termite. Their bodies are a little over .25 inches long. Their wings are paper-y white.

When my neighbor pointed them out to me, they were swarming out from under our outside A/C unit (or pretty close to it). They were thickly carpeting the ground and crawling over everything. (Ugh, I just shudder thinking this.) I thought they might be leafcutters, but nothing I've read about leafcutters implies they would be this far north. I've also not seen anything swarm like this and we've lived in this house for 6 years. The weather was especially humid today and we live in Chicago, if that helps.

I captured two in my daughter's bug jar just in case I can't identify them from the internet. But they are walking around so quickly, I can't get a good photo of them.

posted by jeanmari to pets & animals (9 comments total)

I'm guessing carpenter ants.
posted by HuronBob at 5:35 PM on September 22

Looks like a winged ant. You can see a drawing with a comparison here.
posted by The Light Fantastic at 5:35 PM on September 22

err, it was a drawing...I mean photo...
posted by The Light Fantastic at 5:35 PM on September 22

Flying ants getting busy!
posted by orme at 5:36 PM on September 22

They're probably alates. Remember that word--if you ever start doing crossword puzzles, it's bound to pop up sooner or later.
posted by pullayup at 5:45 PM on September 22

i just caught one of these earlier today (in chicago) and put it in the refrigerator so that I can inspect it more closely at my leisure. I'm guessing it's a young queen of some local ant species. Which species is what I need the leisure to determine. There may also be winged males about.
When I get to inspection, I always go to bugguide.net... I think HuronBob is dead on with guessing Carpenter ant.
posted by Cold Lurkey at 6:09 PM on September 22

But I've seen Carpenter Ants before...and this seems kind of small and reddish for a Carpenter Ant. So far, friends sending emails have mentioned these:

-Swarming Pharaoh Ant
-Swarming Odorous House Ant
-swarming Pavement Ant

But I have no idea how to tell which I have.
posted by jeanmari at 6:20 PM on September 22

When you get down to species of ants, you're basically splitting hairs. You'd need a magnifying glass and knowledge of ant-anatomy. Many species can vary in size and color, carpenter ants included. Your best bet of to find a non-winged ant to identify (which, come to think of it, can also be tricky because they lose their wings pretty easily). Maybe you can narrow it down by region?

If you're a homeowner I might also suggest calling a pest control company for an inspection just to be sure. I could set you up for a free one (I work for terminix), which would actually be a "termite" inspection, but they'd at least be able to tell you what it is. Send me a private message if you'd like.
posted by a.steele at 8:58 PM on September 22

They definitely are not carpenter ants and they probably aren't hurting anything. They are probably a species of ant that goes by the common name of meadow ant or garden ant. Some greenkeepers call them turfgrass ants. I live on the east coast, I don't know what they call them in Chicago. They probably belong to the genus Lasius.

The queens and drones emerge every year on one specific afternoon in the fall. Every colony in your area will launch at the same time so that members of different colonies can mate. Some people call these days "flying ant day".The colony could have been there for years. If you aren't there to witness the launch on that specific afternoon you may never know that the colony is there. If they are in the Lasius genus, the works are much smaller (2-4 mm) than the queens and they many have a much lighter color.

One of the best places for online ant photos is antweb.org. You can check out all the Lasius species that can be found in Illinois here. There are pictures of queens if you click on the species names.
posted by Procloeon at 10:17 PM on September 22