Under most circumstances, an ant bite may hurt but will not be dangerous. There might be a small welt and some itching, but nothing worth seeing a doctor about. The only time you should be concerned is if you are bitten by a fire ant because some people are allergic to the venom. If you thought all fire ants are red, you're mistaken. Black fire ants may not be as common, but their venom is as painful as red fire ants.
Acrobat ants (Crematogaster spp.) are about 1/16 to 1/8 inch long and may be black to light brown in color. Its name comes from its ability to raise its abdomen over its head. Worker acrobat ants have been known to bite aggressively and release a repulsive odor when they are disturbed. Nests are usually outdoors under stones or in the soil and old trees. They can occasionally be found nesting indoors.
Carpenter ants (Camponotus spp.) are about 1/4 to 1/2 inch long and can be black, red, brown or yellow. They are the largest black ant found in homes and are often mistaken for termites. Although carpenter ants will carve out tunnels in wood, their tunnels are smooth and done only to create pathways to the nest. They have strong jaws and will bite if handled, at which time they may inject a formic acid into the wound. Nests are often found in rotten wood, either outdoors or indoors.
Pavement ants (Tetramorium caespitum) are about 1/8 inch long with a brown or black body. Although rarely aggressive, they have the ability to both sting and bite. They usually nest under stones, wood or boards or along sidewalks, cement slabs or foundations. Finding the nest and treating it with an insecticidal dust is usually the only method for control since baiting is rarely effective for these ants.
Black Imported Fire Ants
The black imported fire ant (Solenopsis richteri) is nearly identical to the red imported fire ant (Solenopsis invicta). Both are small ants about 1/8 inch long, but the black imported fire ant is dark brown or black in color as opposed to reddish brown. Black varieties are also less aggressive, which may be why they are not as common. Beyond that, the two ants are nearly identical in characteristics. Fire ants attack by biting their prey and injecting venom with a stinger. Venom causes an intense burning sensation. A white pustule will form at the site within 24 to 48 hours.