Autapomorphies of Stichonodon insignis:

1. Ventral extent of third infraorbital (64): (1> 0) reaching horizontal arm of preopercle. Reversal of synapomorphy 3 of node 180. Paralleled in the Heterocharacinae and Iguanodectinae, in nodes 184, 198, 225, and 302, and in Agoniates anchovia, Brycon pesu, Hasemania nana, Markiana nigripinnis, Moenkhausia sanctaefilomenae, Pseudochalceus kyburzi, and Roeboexodon geryi . Some trees: Reversed in node 292.

2. Dorsal end of laterosensory canal of preopercle and suprapreopercle (82): (0> 1) overlapping anterodorsal process of opercle. Paralleled in the Alestidae, in node 230, and in Bario steindachneri, Hyphessobrycon eques, Parecbasis cyclolepis, and Pristella maxillaris .

3. Length of ascending process of premaxilla (104): (0> 1) reaching just anterior end of nasal. Paralleled in nodes 225 and 294 and in Charax stenopterus and Phenacogaster tegatus . Some trees: Paralleled in Bryconamericus agna .

4. Fossa for inner row of replacement premaxillary teeth (133): (0> 1) present.

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

6. Abrupt decrease in size of dentary teeth (148): (1> 0) absent. Reversal of synapomorphy 1 of node 222.

7. Contact between ectopterygoid and anterodorsal region of quadrate (162): (0> 1) absent. Paralleled in nodes 184 and 242, and in Aphyocharax dentatus, Engraulisoma taeniatum, and Prionobrama paraguayensis . Some trees: Paralleled in the Cheirodontinae and in Microschemobrycon casiquiare .

8. Ventral margin of anterior ceratohyal (179): (1> 0) smooth and without notches. Reversal of synapomorphy 3 of node 189. Paralleled in node 211.

9. Number of gill rakers on first hypobranchial and ceratobranchial (195): (1> 0) 16 or more. Paralleled in nodes 177 and 183 and in Astyanax latens, A. cf. rutilus, A. pelegrini, Hoplias cf. malabaricus, Hyphessobrycon socolofi, Moenkhausia dichroura, Parecbasis cyclolepis, and Piaractus mesopotamicus .

10. Laminar bony ridge on dorsal margin of abdominal ribs (224): (0> 1) present.Paralleled in node 297 and in Parecbasis cyclolepis .

11. Number of dorsal pterygiophores (277): (0> 1) 11 or more. Paralleled in Stethaprion erythrops .

12. Radii of scales (322): (0> 1) converging at focus. Reversal of synapomorphy 7 of the Characidae . Paralleled in node 273 and in Tetragonopterus argenteus . Some trees: Paralleled in node 302 and in Microschemobrycon casiquiare .