Hypostomus, Lacepède, 1803

Ota, Renata Rúbia, Deprá, Gabriel de Carvalho, Graça, Weferson Júnio da & Pavanelli, Carla Simone, 2018, Peixes da planície de inundação do alto rio Paraná e áreas adjacentes: revised, annotated and updated, Neotropical Ichthyology 16 (2), pp. 1-111 : 71

Hypostomus

1. Teeth spoon-shaped..................................... H. cochliodon

1’. Teeth bifid ...................................................................... 2

2. Ground color light-beige, with dark-brown spots and/or dark-brown vermiculate pattern, slightly conspicuous ...... .............................................................................. H. ternetzi

2’.Ground color dark-brown or grey, with several conspicuous light- or dark-brown blotches......................... 3

3. Body covered by light-beige blotches............................. 4

3’. Body covered by dark-brown blotches.......................... 8

4. Premaxilla with eight to 14 and dentary with 10 to 16 teeth.............................................................. H. microstomus

4’. Premaxilla with more than 15 and dentary with more than 16 teeth........................................................................ 5

5. Premaxilla and dentary with 19 to 32 teeth ................... ....................................................................... H. margaritifer

5’. Premaxilla and dentary with more than 32 teeth ........... 6

6. Premaxilla with 35 to 46, and dentary with 34 to 46 teeth; pelvic fin longer or as long as pectoral fin ............... .................................................................... H. albopunctatus

6’. Premaxilla and dentary with more than 48 teeth; pelvic fin shorter than pectoral fin ................................................. 7

7. Premaxilla with 49 to 54 and dentary with 49 to 55 teeth; mid-lateral series with 25 or 26 plates; abdomen with plates concentrated on its central portion .................. ................................................................... H. cf. strigaticeps

7’. Premaxilla with 65 to 110 and dentary with 65 to 132 teeth; mid-lateral series with 28 or 29 plates; abdomen completely covered by plates................................. H. regani

8. Orbit large, its diameter contained 3.9 to 5.5 in head length.................................................................................. 9

8’. Orbit small, its diameter contained 6.5 a 9.5 in head length................................................................................. 10

9. Abdomen completely covered by plates ....... H. hermanni

9’. Abdomen naked or partially covered by plates ............ ............................................................................. H. iheringii

10. Dorsal fin long, its spine length contained 2.6 to 3.4 in standard length .............................................. H. commersoni

10’. Dorsal fin short, its spine length contained 3.9 to 4.3 in standard length.......................................... H. ancistroides