Smaller yellow ant - Lasius claviger

For the record

@ Tristan -- "Geniculate" means elbowed, not clubbed, though many ants also have clubbed antennae (terminal segments bigger and thicker).
Also note that in this case, the queen would not found her own colony, because this is a social parasite species. After mating, she must enter the nest of another Lasius species (most often L. alienus), kill the host queen and become accepted by the workers there, who then raise her first young. Eventually, a pure colony of L. claviger arises.
@ Ken -- Based on the shininess, rich red brown color, head shape, somewhat incrassate forelegs, this does appear to be L. claviger.
@ Kelly -- This ant species normally flies in fall. It may be that cooler temperatures reduce aggression of hte host species and makes it easier for them to invade.

… James C. Trager, 5 February, 2012 - 7:49am

Moved

Moved from Ants.
Thank you all for your VERY helpful comments!

… Kelly Fiegle, 5 February, 2012 - 5:31am

Just wondering...

How did you make the species-level ID? Even assuming that the genus is correct (and I don't have the expertise to make that call), there are evidently more than 40 Lasius species in N.A. Unless you had an expert look at the photo, I'd suggest moving it back to the family level for now. Thanks.

EDIT: Never mind. Looks like Dr. Trager is in agreement. :)

… Ken Wolgemuth, 5 February, 2012 - 7:50am

Moved

Moved from ID Request.

… Ken Wolgemuth, 4 February, 2012 - 4:05pm

Formicidae

Yup, it's an ant. Remember, you can always tell ants by their 1) clubbed antennae (in the literature, this is called "geniculate" antennae. Chalcidids also have it, but they're tiny-sized and have big femorae), and 2) the nodes between the 2nd and 3rd body segments (not visible in the shot).
Cassie's right; this one's just off trying to start her own colony.

… Tristan McKnight, 4 February, 2012 - 12:06pm

ant

Just a guess -- looks like an ant in the genus Lasius.

… Ilona L., 4 February, 2012 - 12:05pm

Ant Reproductive...

Likely a queen that has left to make her own colony. They try to disperse as far as possible.

… Cassie Novak, 4 February, 2012 - 10:35am