Genus Thayeria .

As previously exposed, according to the hypothesis of relationships proposed herein, Thayeria should be transferred to Hemigrammus .

Synapomorphies:

1. Base of second pectoral ray (231): (1> 0) large and partially overlapping base of first pectoral ray from medial view. Paralleled in node 164 and in Moenkhausia dichroura, Prionobrama paraguayensis, and Tetragonopterus argenteus .

2. Position of ventral margin of posttemporal (252): (1> 0) anterior to lateral margin of epioccipital. Paralleled in nodes 162 and 285 and in Aulixidens eugeniae, Creagrutus anary, Diapoma speculiferum, Moenkhausia cf. intermedia, and Pyrrhulina australis . Some trees: Paralleled in node 247 and in Knodus breviceps .

3. Bony hooks on fin rays (307): (1> 0) absent. Paralleled in the Gymnocharacinae, in nodes 207, 283, and 297, and in Astyanax paris, Bryconamericus mennii, Exodon paradoxus, Inpaichthys kerri, Pseudochalceus kyburzi, and Rhoadsia altipinna . Some trees: Paralleled in Hasemania nana and Hyphessobrycon elachys .

4. Color of caudal-fin lobes (345):(0>2) ventral lobe dark brown or black and dorsal lobe hyaline.Paralleled in Hemiodus cf. thayeria .