Bug Identifier
Identification

Types of Ants: 8 Common Species

By the Bug Identifier Editorial Team. Updated September 27, 2026. 4 minute read.

Elbowed antennae and a pinched waist with one or two nodes. This guide covers the 8 ants people find most often.

How to narrow it down

Narrow it down with three quick checks. Count the legs: insects have six, spiders and ticks have eight, and centipedes and millipedes have many more. Check for wings, even folded ones. Then compare size against a coin: a US penny is 19 mm across. Our bug identifier tool does this filtering for you.

The 8 bugs

Red Imported Fire Ant

Red Imported Fire AntSolenopsis invicta2–6 mmHealth risk

A small, aggressive reddish-brown ant that builds dome-shaped mounds of loose soil in sunny lawns and fields across the southern US. When disturbed, workers swarm and sting repeatedly.

Tell-tale sign: Mixed sizes of copper-red workers in one colony. Risk: Fire ant stings burn, form white pustules, and can cause severe allergic reactions in sensitive people.

Argentine Ant

Argentine AntLinepithema humile2–3 mmNuisance

A small, light-to-dark brown ant that forms huge, cooperating supercolonies. Wide, busy trails often stream into kitchens during hot or rainy weather.

Tell-tale sign: Uniform light-brown body with one flat node. Risk: Argentine ants don't sting and rarely bite; they protect aphids and scale insects on garden plants.

Carpenter Ant

Carpenter AntCamponotus pennsylvanicus6–13 mmNuisance

A large black ant that nests in moist or damaged wood, including window frames, decks and wall voids. It doesn't eat wood but excavates smooth galleries and pushes out sawdust-like debris.

Tell-tale sign: Large ant with an evenly rounded, single-arch thorax. Risk: Carpenter ants can deliver a painful bite and weaken wood over time, but they do not carry disease.

Little Black Ant

Little Black AntMonomorium minimum1.5–2 mmNuisance

A tiny, jet-black, shiny ant that nests in lawns, under rocks and in wall voids. Workers form narrow trails to sweets, grease and meats.

Tell-tale sign: Very small, glossy jet-black body. Risk: Little black ants have a sting too weak to feel; they are a nuisance only.

Longhorn Crazy Ant

Longhorn Crazy AntParatrechina longicornis2.3–3 mmNuisance

A dark, slender ant with extremely long legs and antennae that runs in fast, jerky, seemingly random paths. It nests in soil, trash and wall voids, mostly in warm southern states.

Tell-tale sign: Long legs and antennae relative to its body. Risk: Crazy ants rarely bite and don't sting; their sheer numbers make them a nuisance.

Odorous House Ant

Odorous House AntTapinoma sessile2–3 mmNuisance

A small, dark brown to black ant that trails along counters and sinks looking for sweets. Crushed workers give off a smell often compared to rotten coconut.

Tell-tale sign: Small, uniformly dark ant with an uneven thorax. Risk: Odorous house ants are a nuisance only; they rarely bite and don't sting.

Pavement Ant

Pavement AntTetramorium immigrans2.5–4 mmNuisance

A dark brown ant that nests under sidewalks, driveways and slabs, pushing up small piles of sand. Colonies fight noisy battles on pavement in spring.

Tell-tale sign: Parallel grooves on the head and thorax. Risk: Pavement ants have a weak sting that rarely bothers people; they are mainly a nuisance.

Pharaoh Ant

Pharaoh AntMonomorium pharaonis1.5–2 mmNuisance

A tiny, pale yellow ant that nests in warm, hidden spots inside walls, cabinets and appliances. Colonies split into new nests when disturbed, which makes them hard to control.

Tell-tale sign: Very small, light yellow to amber body with a darker abdomen. Risk: They don't bite, but in hospitals and kitchens they can carry bacteria onto clean surfaces.

Which ones should you worry about?

1 of the 8 bugs in this guide can bite or sting. The ones to take seriously are red imported fire ant. The rest are harmless or simply a nuisance.

Comparison at a glance

Red Imported Fire AntArgentine AntCarpenter Ant
GroupAntsAntsAnts
Scientific nameSolenopsis invictaLinepithema humileCamponotus pennsylvanicus
Size2–6 mm2–3 mm6–13 mm
ColorsRed and BrownBrownBlack and Red
Legs6 legs6 legs6 legs
WingsNoNoNo
Bites or stingsBites, StingsNoBites
RiskHealth riskNuisanceNuisance
Key featureMixed sizes of copper-red workers in one colonyUniform light-brown body with one flat nodeLarge ant with an evenly rounded, single-arch thorax

Frequently asked questions

What is the most common one?

Among the bugs in this guide, the red imported fire ant and Argentine ant are the ones people ask about most.

Which of these are dangerous?

Red Imported Fire Ant can be medically significant.

How can I identify a bug I found?

Use the free bug identifier tool: choose the number of legs, wings, main color, size and where you found it, and it will list the closest matches.