Thief Ant
Solenopsis molesta
This record describes Solenopsis molesta (species). Recorded family: Formicidae. Recorded order: Hymenoptera.
Identification and Appearance
See Thompson (1989) below. A very abundant and widely distributed species that goes mostly unnoticed because of its small size.
Identification notes
See Thompson (1989) below.
Classification
- Kingdom
- Animalia
- Phylum
- Arthropoda
- Class
- Insecta
- Order
- Hymenoptera (Ants, Bees, Wasps and Sawflies)
- Superfamily
- Formicoidea
- Family
- Formicidae (Ants)
- Subfamily
- Myrmicinae
- Tribe
- Solenopsidini
- Genus
- Solenopsis (Fire Ants and Thief Ants)
Imported taxonomy record. Source availability varies; see the source references and editorial policy below.
Habitat and Range
Habitat
Moist soil in virtually any location; more likely to be found in sunny spots. Commonly nests in the mounds of other ants, in spaces not occupied by, but close to the brood chambers of the mound builders.
Geographic Range
Throughout NA
Seasonal Activity
mostly Summer, Fall (BG data)
Diet and Behavior
Diet: Generalist scavenger easily attracted to a variety of baits, often feeding on the underside of these, as larger ants feed simultaneously from above. Tends root-sap-feeding hemipterans, and preys on innocent, immobile larvae and pupae, including those of other ants.
Life History
Mating flights occur in the second half of summer, with large flights coinciding with those of common Lasius species near the end of summer. These occur on sunny, calm days following a cooling rain. First workers are raised by single or small groups of queens after these flights.
About Flies: the wider group
Order-level background for Hymenoptera, the group containing Solenopsis molesta. Species-specific details appear above.
Group overview
Hymenoptera includes over 150,000 described species of ants, bees, wasps, and sawflies. Earth harbors approximately 20 quadrillion (20×10^15) ants, with a combined biomass of ~12 megatons of dry carbon - exceeding the combined biomass of all wild birds and mammals (PNAS, 2022).
Ecological role of the group
About 35% of the world's food crops depend on animal pollinators. The chocolate industry, valued at over $100 billion, depends on pollinating flies and midges. Ants are the dominant soil engineers in most terrestrial ecosystems, turning more soil than earthworms in many habitats.
Economic and practical significance of the group
Pollinators contribute $235-577 billion worth of annual global food production (FAO). In the U.S., bee pollination alone benefits crops valued at $18 billion annually, and honey bees are responsible for $5.4 billion in agricultural productivity. Between April 2023-2024, 55.1% of managed honey bee colonies were lost. The U.S. bee population dropped from 5 million to 2.5 million.
Recorded sources for this group: FAO, USDA, EPA, PNAS (2022), US Fish & Wildlife Service. Imported estimates may describe particular regions or reporting periods.
Photos of Thief Ant (5)
Photo credits: Contributed by Nick Fensler; Additional contributions by Mike Quinn | Contributed by Nick Fensler; Additional contributions by Mike Quinn , JohnMaxwell22 , James C. Trager , KenW
Frequently Asked Questions About Thief Ant
What is Thief Ant?
Thief Ant (Solenopsis molesta) is a species in the family Formicidae, within the order Hymenoptera.
How big is Thief Ant?
1.4-1.5 mm workers, males 3.5 mm, queens 3.5-4+ mm depending on state of physogastry.
How do you identify Thief Ant?
See Thompson (1989) below.
Where is Thief Ant found?
| Feature | Details |
|---|---|
| Habitat | Moist soil in virtually any location; more likely to be found in sunny spots. Commonly nests in the mounds of other ants, in spaces not occupied by, but close to the brood chambers of the mound builders. |
| Range | Throughout NA |
What does Thief Ant eat?
The diet of the Thief Ant includes Generalist scavenger easily attracted to a variety of baits, often feeding on the underside of these, as larger ants feed simultaneously from above. Tends root-sap-feeding hemipterans, and preys on innocent, immobile larvae and pupae, including those of other ants..
When is Thief Ant active?
Thief Ant: seasonal activity - mostly Summer, Fall (BG data).
What is the life cycle of a Thief Ant?
Mating flights occur in the second half of summer, with large flights coinciding with those of common Lasius species near the end of summer. These occur on sunny, calm days following a cooling rain. First workers are raised by single or small groups of queens after these flights.