Autapomorphies of Iguanodectes geisleri:

1. Relative length of pterotic spine (46): (0> 1) restricted to attachment region of hyomandibular ligament. Paralleled in node 205.

2. Laterosensory canal in antorbital (72): (0> 1) present. Paralleled in the Bryconops clade and in Brycon falcatus and Chalceus macrolepidotus .

3. Medial anteroventral notch of dentary (114): (0> 1) present. Paralleled in node 209.

4. Maxillary teeth (134): (1> 0) absent. Paralleled in Aulixidens eugeniae, Coptobrycon bilineatus, Parecbasis cyclolepis, and Stichonodon insignis . Some trees: Paralleled in Hyphessobrycon elachys and Psellogrammus kennedyi .

5. 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, Cheirodon interruptus, Coptobrycon bilineatus, and Hyphessobrycon bifasciatus . Some trees: Paralleled in Hasemania nana, Paracheirodon axelrodi, and Parecbasis cyclolepis .

6. Number of gill rakers on first hypobranchial and ceratobranchial (196): (0> 1) ten or fewer. Paralleled in the Characinae and in Bryconops melanurus, Hyphessobrycon pulchripinnis, and Moenkhausia sanctaefilomenae . Some trees: Paralleled in node 196 and in Hemigrammus erythrozonus and Hyphessobrycon herbertaxelrodi .

7. Posterior margin of cleithrum (235): (0> 1) with markedly concave margin, almost forming straight angle.Paralleled in nodes 162, 247, and 253 and in Agoniates anchovia, Attonitus ephimeros, Characidium borellii, Moenkhausia cf. intermedia, Prionobrama paraguayensis, and Xenagoniates bondi .

8. Number of unbranched anal-fin rays (285): (1> 0) three or fewer. Paralleled in node 252 and in Paracheirodon axelrodi .

9. Number of branched anal-fin rays (288): (1> 0) 24 or less. Reversal of synapomorphy 5 of the Characidae . Paralleled in nodes 200, 277, and 300 and in Acestrorhynchus pantaneiro .