Key to Polyrhachis flavicornis-group species from Thailand

Key to species of the Polyrhachis flavicornis species group from Thailand based on the worker caste. Modified from Jaitrong et al. (2023).

1

 * Antennal scape, dorsum of mesosoma, and first gastral tergite without standing hairs
 * Antennal scape, dorsum of mesosoma, and first gastral tergite with dense standing hairs

2

 * Head, mesosoma, and petiole distinctly black Polyrhachis flavicornis
 * Head, mesosoma, and petiole reddish brown Polyrhachis varicolor

3

 * Standing hairs on antennal scape shorter than maximum width of scape; petiole including spines without standing hairs Polyrhachis constructor
 * Standing hairs on antennal scape longer than or as long as maximum width of scape; petiole including spines with dense, long standing hairs Polyrhachis longipilosa