Pristomyrmex punctatus (Smith, F., 1860)

Ordinary workers measure approximately 2.6–3.3 mm in total length. Rare enlarged reproductive individuals, often called ergatoids or “cheaters” in scientific studies, can be noticeably larger than ordinary workers.

Broadly distributed in East and Southeast Asia. Documented records extend from Japan and southern and central China through parts of mainland and island Southeast Asia to Indonesia and New Guinea. The species was originally described from Batjan Island in Indonesia.

Occupies humid ground-level microhabitats. Colonies have been recorded beneath stones, fallen timber and accumulated leaf litter. Japanese populations use temporary shallow nests during warmer months but may overwinter in deeper soil cavities around trees. Colonies show a preference for moist nesting conditions.

Colonies can relocate repeatedly rather than occupying one permanent nest. In studied Japanese populations, movements between temporary nesting sites occurred particularly from June to August. Before winter, colonies move into deeper, more protected soil cavities. Younger workers generally remain inside the nest, while older, non-reproductive workers undertake outside tasks.

A complete field diet has not been quantified in the principal species studies. Laboratory colonies readily consumed sugar and a honey-and-egg-yolk mixture, demonstrating use of both carbohydrate-rich and protein-rich foods. Published field observations also indicate strong competition between colonies around food resources.

Colonies are normally queenless and may contain several thousand workers. Young workers lay a small number of unfertilised eggs that develop into females through thelytokous parthenogenesis. The workers later stop reproducing and undertake other colony tasks. Rare colonies contain enlarged ergatoid females, and males occur occasionally. Some colonies contain more than one clonal lineage, partly because formerly separate colonies can fuse.