Autapomorphies of Cyanocharax alburnus:

1. Development of transverse process of neural arch of third vertebra (219): (0> 1) well developed and extending beyond anterior margin of tripus. Paralleled in node 302, and in Agoniates anchovia, Deuterodon langei, Engraulisoma taeniatum, Hemiodus cf. thayeria, Roeboexodon geryi, and Thayeria obliqua. Some trees: Paralleled in Microschemobrycon casiquiare and Parecbasis cyclolepis .

2. Number of branched pelvic-fin rays (258): (1> 0) six or less. Paralleled in the Aphyocharacinae, in nodes 220, 236, 280, and 302, and in Axelrodia lindeae, Cheirodon interruptus, Hollandichthys multifasciatus, Hoplocharax goethei, and Hyphessobrycon luetkenii . Some trees: Paralleled in Hasemania nana and Hyphessobrycon elachys .

Some trees:

3. Number of gill rakers on first hypobranchial and ceratobranchial (196): (1> 0) 11 or more. (k13-14). Reversal of synapomorphy 5 of node 196. Paralleled in node 237 and in Bryconamericus cf. exodon and B. cf. iheringii . Some trees: Paralleled in the Cheirodontinae .