First evidence of supercolony traits in the subfamily Ponerinae: The invasive Odontomachus troglodytes populations in Taiwan
A new study from the laboratory of Dr. Shu-Ping Tseng (Department of Entomology, National Taiwan University) reports the first confirmed case of supercolony traits in the ant subfamily Ponerinae. The work, conducted by Hsiao-Yang Chu as part of his master’s thesis under Dr. Tseng’s supervision, has been published in Myrmecological News.
Many invasive ants form “supercolonies” — vast cooperative networks of nests that show no aggression toward each other, often featuring multiple queens (polygyny) and multiple nests (polydomy). This social organization facilitates rapid expansion and ecological dominance, and has been widely reported among Formicoid lineages such as Argentine ants and long-legged ants. However, it had never been formally confirmed in the more evolutionarily basal Poneriod clade.
Through behavioral assays and newly developed microsatellite markers, the team investigated Odontomachus troglodytes populations invading southern Taiwan (Kaohsiung and Chiayi). The results revealed that the Kaohsiung population displays classic supercolony traits:
Lack of aggression between nests
Multi-queen and multi-nest structure
Colony boundaries extending up to 6.9 km
Genetic analyses further showed frequent multiple mating events and a high proportion of diploid males, likely linked to population bottlenecks and inbreeding during invasion. The Chiayi population exhibited lower genetic diversity and lacked private alleles, suggesting that the invasion originated in Kaohsiung and later spread northward.
This research provides new insight into how invasive ants within Ponerinae may evolve complex social systems, offering an important perspective for future studies on invasion ecology and control strategies.