Invasive Insects: Risks and Pathways Project ASIAN NEEDLE ANT UPDATED: JUNE 2019 Invasive insects are a huge biosecurity challenge. We profile some of the most harmful insect invaders overseas to show why we must keep them out of Australia. Species Asian needle ant / Pachycondyla chinensis. Also Brachyponera chinensis. Main impacts Displaces native ants from forests, leading to declines in plants that require ant dispersal of their seeds, as well as declines of ants. Has a painful sting and causes severe allergic reactions in some people. Native range China, Taiwan, North Korea, South Korea, Japan.1 Invasive range United States, Russia, Georgia.1 Main pathways of global spread Unknown, but there are records of interceptions on plant materials.1 ENVIRONMENTAL IMPACTS OVERSEAS In the United States the Asian needle WHAT TO LOOK OUT FOR ant has penetrated undisturbed native Asian needle ants are dark brown to black with orange-brown mandibles, legs, forests, including in national parks and antennae and stingers. The workers are 3.5 to 5.0 mm long. They are flexible about state parks, where it displaces a range of where they nest – in forests, they typically live in logs or under rocks and leaves; in native ants2. Surveys in North Carolina urban areas they can nest in potted plants, piles of mulch and underneath door mats. found it was twice as abundant as all Photo: Chris Hartley native ant species combined and the richness of native ant species was lower (by about a third) than in uninvaded the most important seed dispersing 2 HUMAN AND areas . The needle ant may achieve ant, the ‘dominant keystone’ winnow high abundance in part because of its ant (Aphaenogaster rudis), probably ECONOMIC IMPACTS 2,12 efficiency at hunting termites . In a both by killing its workers and reducing OVERSEAS laboratory study, the Asian needle ant the availability of termite prey2,3,12. The Asian needle ants have been identified 12 completely destroyed termite nests . dispersal abilities of the affected plants as a public health threat in the United This may reduce termite abundance in are limited, their germination rates are States because of their stings, incurred invaded areas, with consequences for low, and they are known to be sensitive in gardens and wooded areas1,5. Victims rates of decomposition. to disturbance2. Without the winnow ant, have described the sting as an intense About a third of the understorey plant their seeds are vulnerable to being eaten pain that fades and returns frequently species in eastern North American by rodents or failing to grow because over several hours, often in areas 4 5 forests rely on ants for seed dispersal, a of shading by their parent plants . The beyond the original sting site . Some service not provided by the Asian needle understorey of forests is changing as a suffer anaphylactic shock, as reported 3 ant2. In some sites in North Carolina, consequence . in medical papers from China, Japan, 1 the needle ant completely displaces South Korea and the United States , with symptoms including generalised INVASION WATCH: Asian needle ant Asian needle ant. Photo: © Matt Bertone urticaria, respiratory distress, wheezing In the United States this ant has been Journal of Allergy and Clinical Immunology. and hypotension with or without loss of recorded from Florida, Alabama, 107: 1095–1099. consciousness6. Some health problems Arkansas, New York State, Wisconsin 7. Berg R (1975): Myrmecochorous plants in attributed to fire ants in the United States and Washington State, indicating Australia and their dispersal by ants. Australian may be due to Asian needle ants, which wide climatic tolerances, which would Journal of Botany. 23: 475. have received far less publicity1. translate into a wide distribution in 8. Rice B, Westoby M (1986): Evidence against eastern and southern Australia. the hypothesis that ant-dispersed seeds reach nutrient-enriched microsites. Ecology. 67: AUSTRALIAN 1270–1274. CONCERNS SOURCES 9. Lengyel S, Gove AD, Latimer AM, Majer Australia has more ant-dispersed plants 1. Guénard B, Wetterer JK, MacGown JA (2018): JD, Dunn RR (2010): Convergent evolution of than any other region of the world7,8. Global and temporal spread of a taxonomically seed dispersal by ants, and phylogeny and challenging invasive ant, Brachyponera biogeography in flowering plants: a global Invasion by Asian needle ants could chinensis (Hymenoptera: Formicidae). Florida survey. Perspectives in Plant Ecology, Evolution cause substantial disruptions to habitats Entomologist. 101: 649–656. and Systematics. 12: 43–55. and plant declines and extinctions if 2. Guénard B, Dunn RR (2010): A new (old), 10. Berg R (1975): Myrmecochorous plants in seed-dispersing ants are displaced, invasive ant in the hardwood forests of eastern Australia and their dispersal by ants. Australian as has occurred in those parts of the North America and its potentially widespread Journal of Botany. 23: 475. United States that have been studied. impacts. (A. Traveset, editor) PLoS ONE. 5: 11. NSW Threatened Species Scientific The Australian plants dependent on e11614. NSW threatened species and 9 Committee (2019): ant dispersal occur in 78 genera and 3. Warren RJ, McMillan A, King JR, Chick L, ecological communities listed in the schedules include many ecologically important, Bradford MA (2015): Forest invader replaces of the Biodiversity Conservation Act, 2016. NSW iconic and rare species, including wattles, predation but not dispersal services by a Government Office of Environment & Heritage. pea bushes, boronias, guinea flowers keystone species. Biological Invasions. 17: Retrieved from https://www.environment.nsw. and fringed lilies, all of which could 3153–3162. gov.au/resources/threatenedspecies/nsw- be expected to become less common 4. Rodriguez-Cabal MA, Stuble KL, Guénard threatened-species-ecological-communities- if they lose ant dispersal services10. B, Dunn RR, Sanders NJ (2012): Disruption of listed-schedules-20190201.pdf. At special risk are all the threatened ant-seed dispersal mutualisms by the invasive 12. Bednar DM, Shik JZ, Silverman J (2013): plant species in genera that rely on ant Asian needle ant (Pachycondyla chinensis). Prey handling performance facilitates dispersal. Examples in NSW include Biological Invasions. 14: 557–565. competitive dominance of an invasive over Behavioral Ecology Bertya (4 species), Boronia (7 species), 5. Nelder MP, Paysen ES, Zungoli PA, Benson native keystone ant. 24: 1312–1319. Hibbertia (10 species) and Pomaderris (16 EP (2006): Emergence of the introduced ant species)11. The arrival of these ants could Pachycondyla chinensis (Formicidae: Ponerinae) also put some native ant species at risk. as a public health threat in the southeastern United States. Journal of Medical Entomology. ABOUT THIS PROJECT The Asian needle ant is unusual among 43: 1094–1098. The Invasive Insects: Risks and invasive ants in that it can dominate Pathways Project is a partnership 12 6. Kim S-S, Park H-S, Kim H-Y, Lee S-K, Nahm relatively undisturbed forests , so it can between Monash University and the Invasive D-H (2001): Anaphylaxis caused by the new be expected to invade national parks and Species Council. To find out more visit ant, Pachycondyla chinensis: Demonstration invasives.org.au/risks-and-pathways. nature reserves. of specific IgE and IgE-binding components. INVASION WATCH: Asian needle ant.