New records of riffle beetles in Vietnam (Coleoptera, Elmidae)

We present the first records of the riffle beetles Cuspidevia pilosa Bian, Hu & Tong, 2024 and Macronevia simplex (Hinton, 1936), and new records of Macronychus reticulatus Čiampor & Kodada, 1998, from central and northern Vietnam. The type locality of C. pilosa lies in southern China, while that of M. reticulatus is in southern Laos, and M. simplex in Western Malaysia. We provide DNA barcoding data ( COI ), along with illustrations of the habitus, aedeagi, and biotopes, as well as distribution maps of these species.