Crazy Ants.

The crazy ant is extremely easy to identify on sight by observing its rapid and erratic movements. Confirmation may be made with the aid of a hand lens through which the extremely long antennal scape, long legs and erect setae are very apparent. The slender-bodied, long-legged worker is capable of extremely rapid movement.

Latin Name

Paratrechina longicornis (Latreille)

Appearance

The crazy ant worker is relatively small (2.3-3 mm). The head, thorax, petiole and gaster are dark brown to blackish (Creighton, 1950); the body often has faint bluish iridescence. The body has long, coarse, well-scattered, sub-erect to erect, grayish or whitish setae.

Habitat

The crazy ant occurs in large numbers in homes or outdoors. Ants of this species often forage long distances away from their nests, so nests are often difficult to control.

http://entnemdept.ufl.edu/creatures/urban/ants/crazy_ant.htm