Argentine ant vs Pavement ant
These two are easy to mix up. Here's how to tell an argentine ant from a pavement ant, and whether either one bites or stings.
Argentine ant
Linepithema humile
Pavement ant
Tetramorium immigrans
≠The key differences
Pavement ants usually have two petiole nodes and small spines on the thorax; pavement ants are often darker and show more aggressive behavior between colonies.
⚖︎Side by side
| Argentine ant | Pavement ant | |
|---|---|---|
| To humans | Non-toxic | Non-toxic |
| Size | Workers 2-3 mm, queens about 4-6 mm | Workers 2.5-4 mm; queens 6-8 mm |
| Colours | Brown, Light brown, Dark brown (nearly black) eyes and mandibles | Brown, Dark brown, Black |
| Family | Formicidae | Formicidae |
| Habitat | Urban areas, gardens, agricultural fields, coastal scrub and other disturbed habitats. Nests in soil, leaf litter, under objects, and indoors in moist cavities. | Urban and suburban areas: cracks in pavement and sidewalks, under stones, curbs, building foundations, lawns and occasionally inside buildings. |
| Range | Native to southern South America; invasive in North America, Europe, Africa, Australia, parts of Asia and many islands worldwide. | Native to Europe and parts of Asia; introduced and common across North America and other temperate regions worldwide. |
| Active | Year-round in warm climates and indoors; most active in spring through autumn outdoors and during warm periods of the day. | Spring through fall (most active during warm months); workers forage day and night depending on temperature. |
| Pest? | Yes | Yes |
🔍How to spot an argentine ant
- Workers 2-3 mm long, uniformly brown to dark brown and relatively slender.
- Single petiole node (one small bump) between thorax and abdomen; no spines on the thorax.
- Form long, persistent foraging trails and large numbers at sources of sugar (sweets, honeydew).
- Colonies show low aggression between neighboring nests (supercolonies) where present.
🔍How to spot a pavement ant
- Small workers 2.5-4 mm, uniformly brown to dark brown with a slightly darker gaster.
- Two petiole nodes (two-segmented waist) and two short spines on the rear of the mesosoma.
- Head and thorax show fine parallel sculpturing; antennae with 12 segments and a 3-segmented club.
- Nests in cracks in pavement, along foundations and under stones; look for worker trails at nest entrances.
?Frequently asked questions
What is the difference between an argentine ant and a pavement ant?
Pavement ants usually have two petiole nodes and small spines on the thorax; pavement ants are often darker and show more aggressive behavior between colonies.
Is an argentine ant or a pavement ant more dangerous?
Argentine ant: Non-toxic. Pavement ant: Non-toxic. Argentine ants do not have a sting. Pavement ants do not have dangerous venom.
Identification from photos is never certain: don't handle insects you can't identify, and get medical advice for bites, stings or allergic reactions.