Autapomorphy of Hemibrycon dariensis:

1. Number of cusps of anterior maxillary teeth (139): (0> 1) five or more cusps. Paralleled in the Rhoadsiinae, in nodes 273, 283, and 294, and in Bramocharax bransfordii, Brycon orbignyanus, Gymnocharacinus bergii, Hyphessobrycon pulchripinnis, and Odontostoechus lethostigmus . Some trees: Paralleled in node 246.