Rhinopetitia, Gery, 1964

Menezes, Naércio A. & Netto-Ferreira, Andre L., 2019, A systematic review of Rhinopetitia Géry (Teleostei, Characiformes, Characidae) with descriptions of four new species and redescription of R. myersi Géry, Zootaxa 4700 (1), pp. 59-86 : 61-62

Key to the species of Rhinopetitia

1. Teeth of the outer premaxillary series with seven to nine cusps.................................... R. potamorhachia

1’. Teeth of the outer premaxillary series with three to five cusps.................................................. 2

2. Gill rakers rudimentary on the anterior and posterior parts of first gill-arch ( Fig. 3 ), 8–12 on external row of first gill-arch (upper Rio Tocantins basin)......................................................................... R. paucirastra

2’. Gill rakers well-developed on the anterior and posterior parts of first gill-arch, 13–19 on external row of first gill-arch..... 3

3. Four longitudinal scale rows from dorsal-fin origin to lateral line (upper Rio Xingu and Jamanxim basins)...... R. oligolepis

3’. Five longitudinal scales rows from dorsal-fin origin to lateral line............................................... 4

4. Lateral line scales 32–34; circumpeduncular scales 12 (Rio Tocantins-Araguaia basin)........................ R. myersi

4’. Lateral line scales 35–39; circumpeduncular scales 13–14..................................................... 5

5’. Strongly marked somewhat oval humeral blotch onto scales of 3 longitudinal series; mid-lateral stripe faint and narrow; body depth 25–31% of standard length ( Fig. 4 ) (Rio Tapajós and Xingu basins)......................... R. melanohumeralis

Figures

FIGURE 3. (a) Rhinopetitia myersi, MZUSP 105536, male, 34.0 mm SL, and (b) R. paucirastra, MZUSP 95063, female, 32.0 mm SL. Lateral view (left side) of first gill arches displaying gill rakers.

FIGURE 4. Body depth as a function of standard length for the species of Rhinopetitia.