Autapomorphies of Cheirodon interruptus:

1. Lateral coverage of dilator fossa by sixth infraorbital (69): (0> 1) leaving a conspicuous naked area in anterior region of dilator fossa. Reversal of synapomorphy 1 of the Cheirodontinae .

2. Number of maxillary teeth (135): (1> 0) only one, or absent. Paralleled in the Astyanax clade, in nodes 284 and 290, and in Aulixidens eugeniae, Coptobrycon bilineatus, Hyphessobrycon bifasciatus, and Iguanodectes geisleri . Some trees: Paralleled in Hasemania nana, Paracheirodon axelrodi, and Parecbasis cyclolepis .

3. Rows of gill rakers on first ceratobranchial (192): (0> 1) two. Reversal of synapomorphy 3 of node 179. Paralleled in the Iguanodectinae, in node 280, and in Brycon orbignyanus, Bryconaethiops macrops, Carlana eigenmanni, Hoplocharax goethei, Hyphessobrycon elachys, Odontostilbe microcephala, Parecbasis cyclolepis, Prodontocharax melanotus, and Rhaphiodon vulpinus . Some trees: Paralleled in node 249 and in Attonitus ephimeros .

4. Posterior margin of cleithrum (234): (1> 0) without concavity ventral to first postcleithrum. Reversal of synapomorphy 2 of node 196. Paralleled in node 298 and in Inpaichthys kerri .

5. 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, Cyanocharax alburnus, Hollandichthys multifasciatus, Hoplocharax goethei, and Hyphessobrycon luetkenii . Some trees: Paralleled in Hasemania nana and Hyphessobrycon elachys .