A new species of from Vietnam and an updated key to species of the genus (Hymenoptera, Apidae).

The rare bee genus Lieftinck, 1974 is recorded for the first time from Vietnam. The genus is represented by a new species, Tran, Engel & Nguyen, , from Cao Bang Province and can be most easily confused with Wu from China. The species is most easily differentiated by the unique form of the male terminalia but can also be distinguished by differences in integumental and setal coloration. A revised key is provided to the species of the genus. Females of the new species were collected at flowers of Wall. and DC. (Actinidiaceae); males were collected at flowers of L. (Verbenaceae).