Identifying ants

We have a bit of an ant problem in the house (it started about the same time as all the rain a few months ago, so I think they all headed for shelter–our shelter). The poison we have hasn’t really nuked them back to the stone age, so I set out tonight to identify the buggers. They are really really small as evidenced by my macro shot. The bumps on the background there are from a napkin and from what I have read the ants max out at 1/8th”.

Identifying a creature this small is insane–the difference between an Argentine and an Odorous is a Petiole with or without an errect node. Whatever that means. Here is the site I tried to use, but I think it would be best to have a scanning electron microscope before attempting to follow their tool.