A new hygropetric genus of Heptageniidae from southern China (Insecta, Ephemeroptera)

A small waterfall in Yunnan Province, China, was sampled for heptageniid nymphs and an unknown species was found, which is characterised by having expanded femora and short tibiae, tarsi, and lamellae of gills I. Furthermore, the reared male imagos have longer hindtarsi than tibiae and almost totally fused penes. Based on these key characters and the hygropetric particularity of the new species, a new genus is established in the subfamily Ecdyonurinae. Molecular and morphological evidence demonstrate Brachypodus quadratus gen. et sp. nov. is closely related to Thalerosphyrus and Atopopus. Two modified keys to common Oriental genera in the subfamily Ecdyonurinae are also provided.