Key to Chinese species of the Hesperus borneensis group

1 Head black; head and pronotum without microsculpture....................................................... 2

– Head orange red; head and pronotum with distinct and profound microsculpture................................... 3

2 Pronotum black; abdomen with segments III– V orange red........................................... H. birmanus

– Pronotum orange red; abdomen with segments III– VI orange red............................... H. susannekontrusae

3 TL/EYL: 0.84–1.03; antennomeres 9–11 creamy white............................................. H. watanabei

– TL/EYL: 0.81; antennomeres 8–11 creamy white............................................... H. flexibilis sp. n.