In Louisiana, there are several ant species that are capable of stinging besides the red imported fire ant (Solenopsis invicta), such as the elongate twig ant (Pseudomyrmex gracilis), Comanche harvester ant (Pogonomyrmex comanche) and several species in the subfamily Ponerinae. The Asian needle ant (ANA) (Brachyponera chinensis) joins the list and has been confirmed in the state. Recent reports on the Asian needle ant by Mississippi State University extension entomologist, Santos J. Portugal and other urban entomologists in the region spurred the authors at Louisiana State University to investigate the presence of ANA in their state. By happenstance, two citizen scientists had reported sightings of the ant on iNaturalist at two Louisiana parks in August 2024 and June 2025. Therefore, on June 17, 2025, an LSU entomologist visited one of the parks to ground-truth the citing by collecting the ant, as he had prior experience with it. The Asian needle ant is a termite specialist, preferentially feeding on them, often living in close proximity with termite colonies and inside damp wood. To collect the ants, water-soaked wood was located in a forested area, broken open, revealing ANA, and they did not react aggressively to the disturbance. The ants immediately grabbed immature larva and retreated into crevices, not bothering the collectors at all. Upon retrieval, an LSU entomologist used a microscope at 40x to 60x magnification and the dichotomous key authored by MacGown (2003) to confirm that the collected specimens were ANA. It is important to verify the identity of invasive species submitted on citizen scientist projects as the images may not be of sufficient quality to get a positive identification.

The ANA was discovered in the U.S. in 1934 while individuals were researching Argentine ants (Linepithema humile). Since the introduction of the ANA, it has spread to many states within the U.S., ranging from Wisconsin to Texas to the east coast. ANAs are medium sized (about 5 mm long) and slender. The species originated from Asia. Queens are slightly larger (6.5 mm) and look similar in appearance to workers. ANAs are black to dark brown in coloration, with light brown legs, mandibles and antennae. To distinguish the ant from other look-alikes, ANA has a large single petiole node that extends above the thorax or alitrunk, and a shiny mesopluron on the side of the thorax.

ANA colonies are typically small in numbers, up to a few thousand individuals in large colonies. They are polygynous, meaning they have multiple queens. ANAs use a unique foraging behavior, where the worker carries another worker to a food resource, then drops off the worker to assist in food transport. ANAs do not form mounds, but instead nest in damp, high humidity areas, such as rotting logs, void spaces, under rocks and in leaf litter. They are typically found in forested areas. They also form multiple colonies within an area, which is called polydomy. ANAs swarm during the spring and early summer, although this time range may vary for Louisiana. People typically encounter the ants when they are working with wet wood or digging in moist soil. This is when someone may potentially be stung, although they are not aggressive. The sting is reported similar to that of a honeybee. Individuals who are allergic to stings may have a life-threatening anaphylactic response if stung by the ant, which requires medical attention. Wearing gloves is adequate protection from ANA stings while working with rotten wood or soil in infested areas. People who are sensitive to other insect stings should be aware of the potential for ANA stings and carry an approved rescue device for severe allergenic responses.

In addition to feeding on termites, the Asian needle ant will feed upon beetles, craneflies, springtails and native ants found in their preferred habitats. Because of their ability to prey upon native ants, they can impact native species that deposit seeds in the soil, thus reducing floral diversity. Therefore, ANA is capable of reducing both native animal and plant diversity in infested areas.

While ANA may have been established in Louisiana for some time, there are several other invasive ants in the state, which may have suppressed their populations. Ants have not been surveyed in the state since Shawn Dash’s thesis work at the Louisiana State University almost 20 years ago (2005). It is important to note that ANA management in an area may or may not be needed and total elimination of this ant species in the U.S. is impossible given its cryptic tendencies and preferred habitats. In some states ANA has been reported to forage indoors. Therefore, if management is needed for suspected infestations, correct identification is a necessary first step. Request identification assistance from your local LSU AgCenter Extension agent or the LSU Department of Entomology. If management is needed, it is recommended to use label-approved ant scatter baits in a few target areas where they are foraging followed by an observation period to determine if ants are accepting the baits. Follow label directions. After about a month, this can be repeated if ANA is still active in that location. Application in the spring and in areas of ant activity are more effective. If you have any questions, please contact the LSU Department of Entomology.

Authors

Aaron R. Ashbrook, Chris E. Carlton, Gerardo Guevara-Milla, Stephen Baca, Victoria Bayless

References

• Dash, S.T. 2005. Species Diversity and Biogeography of Ants (Hymenoptera: Formicidae) in Louisiana, with Notes on their Ecology. M.S. Thesis, Louisiana State University, Baton Rouge, LA, pp. 290.
• Guénard, B. and Dunn, R.R. 2010. A New (Old), Invasive Ant in the Hardwood Forests of Eastern North America and Its Potentially Widespread Impact. PLoS ONE 5(7): e11614. doi:10.1371/journal.pone.0011614
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Asian needle ant (Brachyponera chinensis) worker. Photos by Louisiana State Arthropod Museum