Autapomorphies of Pristella maxillaris:

1. Synchondral articulation between lateral ethmoid and anterodorsal border of orbitosphenoid (35): (1> 0) present. Paralleled in the Aphyocharacinae and in Leporinus striatus, Mimagoniates rheocharis, and Rhaphiodon vulpinus .

2. Anterior paired projections of parasphenoid (40): (1> 0) absent. Some trees: Paralleled in Hasemania nana .

3. Anterior region of third infraorbital (63): (0> 1) abruptly expanded relative to posterior region of second infraorbital. Paralleled in node 295.

4. 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 Stichonodon insignis .

5. Number of cusps of anterior maxillary teeth (138): (1> 0) conical, a single cusp. Some trees: Paralleled in Aphyodite grammica and Axelrodia lindeae .

6. Separation between posterior dentary teeth (147): (0> 1) more than width of these teeth. Paralleled in node 221 and in Astyanax cf. rutilus and Aulixidens eugeniae .

7. Articulation between ventral margin of metapterygoid and posterodorsal margin of quadrate (155): (0> 1) present. Paralleled in nodes 176 and 299 and in Deuterodon langei, Heterocharax macrolepis, Roeboides descalvadensis, and Thoracocharax stellatus .

8. Form and degree of ossification of first ceratobranchial gill rakers (200): (0> 1) rather thick and completely ossified distal region. Paralleled in nodes 176, 212, and 299 and in Hoplias cf. malabaricus and Prionobrama paraguayensis .

9. Distribution of denticles on gill rakers (202): (0> 1) along entire surface of gill rakers. Paralleled in node 269 and in Astyanax correntinus, Deuterodon langei, Hoplias cf. malabaricus, and Hyphessobrycon eques .

10. Contact between dorsal margin of adductor mandibulae and ventral margin of dilator operculi (335): (1> 0) absent. Paralleled in Creagrutus anary, Inpaichthys kerri, Piabucus melanostomus, Prionobrama paraguayensis, Prodontocharax melanotus, and Pyrrhulina australis . Some trees: Paralleled in Hyphessobrycon elachys .