The ant subgenus Campomyrma of the genus Polyrhachis Smith, 1857 (Hymenoptera, Formicidae, Formicinae) in Thailand and Laos, with descriptions of two new species.

The subgenus Campomyrma Wheeler, 1911 of the genus Polyrhachis Smith, 1758 in Thailand and Laos is reviewed. Four species are recognized, of which two are described and illustrated as new to science based on the worker and dealate queen under the names Polyrhachis quadrispinosa Jaitrong & Noon-anant, sp. nov. (found in a dead twig on a rubber tree) and P. lao Jaitrong & Yamane, sp. nov. (collected in dead wood). Polyrhachis sukarmani Kohout, 2007 is recorded for the first time from Thailand. A key to the Thai and Lao species of the subgenus based on the worker caste is given.