Both the male and female imagines of Platybaetis selvai Kubendran, Vasanth & Subramanian, 2021 are described for the first time, some key characters of nymphs are also presented. Nymphs of this species have 10-11 segments of terminal filament, and its imagines have the palest bodies among the known five imagines, but their wings have pigmented basal half. Its relatively large body and colorful imaginal wings, and long terminal filament of nymphs can be seen its plesiomorphies.