A cladistic analysis of Eubriancinae was performed, using 21 characters from external morphology (eight from larvae, four from pupae, and nine from adults), and considering Psepheninae as the outgroup. The analysis yielded nine equally parsimonious cladograms (47 steps, CI = 56, RI = 68), and a strict consensus cladogram was calculated (51 steps, CI = 56, RI = 61). The result suggests that the phylogenetic relationships between genera within the subfamily are monophyletic, despite their ecological diversity. The strict consensus cladogram indicates that the genus Heibrianax is paraphyletic to Eubrianax. The monophyly of Heibrianax Eubrianax is supported by three synapomorphic characters. Therefore, Heibrianax is regarded as a junior synonym of Eubrianax. The current article also deals with some members of Eubrianax, although they display significant difference from other representatives of the genus. The evolution of characters in the immature stages is discussed. Eubrianax pellucidus species group and E. serratus species group are treated. Eubrianax manakikikuse amamiensis Satô, 1965 is raised to specific rank. A new subspecies, Eubrianax manakikikuse kimurai ssp. nov., and a new species, Eubrianax serratus sp. nov., are described. Keys to genera of the subfamily, based on adults, larvae, pupae, and a checklist of the species are provided.