Metanotal groove varying from feeble to distinct. Posterior border of propodeum rounded or with a pair of blunt processes. Petiole usually with a large, vertically lamellate subpetiolar process. Legs relatively short. Middle and hind legs lacking tibial spurs.
Most species have monomorphic workers, but in some the workers are polymorphic.
Some have ergatoid females. Although the biology of this genus is poorly known, the workers of at least some species are predators of insect larvae. Most species nest in decaying wood or under bark in forests. For this reason it is excluded from the accompanying worker-based key to Japanese species. We consider the distribution of this taxon to be questionable, and exclude it from consideration here.