Pheidole sp. (undescribed)

The largest big-headed ant in Taiwan, with queens up to 1 cm long. Several queens often found a nest together, but as the colony develops it may trim down to a single queen. Soldiers have very robust heads and reach 9 mm, and workers are 3–4.5 mm. The body is deep reddish brown. It lives mainly in the soil of primary forest at around 500 m in northern Taiwan and is a fierce, active predator that recruits nestmates to capture prey. It closely resembles Pheidole sinica from China but still differs, so it remains an undescribed species.