Pavement Ants (Tetramorium caespitum) have a two-segmented petiole, compound eyes, one pair of spines on the thorax, 12 segmented antenna with a three-segmented club at the end, a sting, and numerous parallel ridges running lengthwise down the head and thorax. Workers are monomorphic, 1/10 to 1/8 in. long, light brown to black, with the legs and antenna slightly lighter in color. An average colony contains about 11,000 workers and is usually found outdoors under stones, along the edges of curbing and under pavement, especially when the pavement is next to a lawn. I have found large numbers of these ants at the bottom of brick facades in Albuquerque homes and beneath weather stripping under doors.