Rediscovery after two decades and geographic range extension of the rare mayfly species, Behningia baei McCafferty & Jacobus, 2006 (Ephemeroptera, Behningiidae) from Thailand

Behningia baei McCafferty & Jacobus, 2006 was originally described from Phitsanulok Province, Thailand, based on nymphs collected in 2002, but no other information has since been added. Two decades later, in 2024, nymphs of B. baei were rediscovered in the Mae Chaem River, Chiang Mai Province. This discovery represents a northern geographic range extension of this species. We provide a photograph of the B. baei nymph and a distribution map for this species.