| Nominal Species (n = 51) | Present allocation (n = 40) | Ref. |
|---|---|---|
| Gymnotus albus Pallas, 1769 | Gymnotus carapo | 26457 |
| Gymnotus anguillaris Hoedeman, 1962 | Gymnotus anguillaris | 12225 |
| Gymnotus arapaima Albert & Crampton, 2001 | Gymnotus arapaima | 41292 |
| Gymnotus ardilai Maldonado-Ocampo & Albert, 2004 | Gymnotus ardilai | 54466 |
| Gymnotus bahianus Campos-da-Paz & Costa, 1996 | Gymnotus bahianus | 30502 |
| Gymnotus brachiurus Bloch, 1786 | Gymnotus carapo | 26457 |
| Gymnotus capanema Milhomem, Crampton, Pierczeka, Shetka, Silva & Nagamachi, 2012 | Gymnotus capanema | 89487 |
| Gymnotus capitimaculatus Rangel-Pereira, 2014 | Gymnotus capitimaculatus | 96661 |
| Gymnotus carapo Linnaeus, 1758 | Gymnotus carapo | 36692 |
| Gymnotus carapo (non Linnaeus, 1758) | Gymnotus omarorum | 82430 |
| Gymnotus cataniapo Mago-Leccia, 1994 | Gymnotus cataniapo | 26457 |
| Gymnotus chaviro Maxime & Albert, 2009 | Gymnotus chaviro | 83382 |
| Gymnotus chimarrao Cognato, Richer-de-Forges, Albert & Crampton, 2008 | Gymnotus chimarrao | 75065 |
| Gymnotus choco Albert, Crampton & Maldonado-Ocampo, 2003 | Gymnotus choco | 49716 |
| Rhamphichthys cingulatus Brind, 1935 | Gymnotus coatesi | 36985 |
| Gymnotus coatesi La Monte, 1935 | Gymnotus coatesi | 26457 |
| Gymnotus coropinae Hoedeman, 1962 | Gymnotus coropinae | 52004 |
| Gymnotus coropinae (non Hoedeman, 1962) | Gymnotus anguillaris | 52004 |
| Gymnotus curupira Crampton, Thorsen & Albert, 2005 | Gymnotus curupira | 55508 |
| Gymnotus cylindricus La Monte, 1935 | Gymnotus cylindricus | 26457 |
| Gymnotus diamantinensis Campos-da-Paz, 2002 | Gymnotus diamantinensis | 42925 |
| Gymnotus electricus Linnaeus, 1766 | Electrophorus electricus | 37075 |
| Gymnotus esmeraldas Albert & Crampton, 2003 | Gymnotus esmeraldas | 49716 |
| Gymnotus fasciatus Pallas, 1769 | Gymnotus carapo | 26457 |
| Giton fasciatus pantherinus Steindachner, 1908 | Gymnotus pantherinus | 26457 |
| Gymnotus henni Albert, Crampton & Maldonado-Ocampo, 2003 | Gymnotus henni | 49716 |
| Carapus inaequilabiatus Valenciennes, 1839 | Gymnotus inaequilabiatus | 26457 |
| Gymnotus interruptus Rangel-Pereira, 2012 | Gymnotus interruptus | 93136 |
| Gymnotus javari Albert, Crampton & Hagedorn, 2003 | Gymnotus javari | 49716 |
| Gymnotus jonasi Albert & Crampton, 2001 | Gymnotus jonasi | 41292 |
| Carapus macrourus Cuvier, 1870 | Gymnotus carapo | 33021 |
| Gymnotus maculosus Albert & Miller, 1995 | Gymnotus maculosus | 36692 |
| Gymnotus mamiraua Albert & Crampton, 2001 | Gymnotus mamiraua | 41292 |
| Gymnotus melanopleura Albert & Crampton, 2001 | Gymnotus melanopleura | 41292 |
| Electrophorus multivalvulus Nakashima, 1941 | Electrophorus electricus | 37075 |
| Gymnotus obscurus Crampton, Thorsen & Albert, 2005 | Gymnotus obscurus | 55508 |
| Gymnotus omarorum Richer-de-Forges, Crampton & Albert, 2009 | Gymnotus omarorum | 82430 |
| Gymnotus onca Albert & Crampton, 2001 | Gymnotus onca | 41292 |
| Gymnotus panamensis Albert & Crampton, 2003 | Gymnotus panamensis | 49716 |
| Gymnotus pantanal Fernandes, Albert, Daniel-Silva, Lopes, Crampton & Almeida-Toledo, 2005 | Gymnotus pantanal | 54472 |
| Gymnotus paraguensis Albert & Crampton, 2003 | Gymnotus paraguensis | 49716 |
| Gymnotus pedanopterus Mago-Leccia, 1994 | Gymnotus pedanopterus | 26457 |
| Gymnotus putaol Lacepède, 1800 | Gymnotus carapo | 26457 |
| Gymnotus regius Chiaje, 1847 | Electrophorus electricus | 26457 |
| Gymnotus stenoleucus Mago-Leccia, 1994 | Gymnotus stenoleucus | 26457 |
| Gymnotus sylvius Albert & Fernandes-Matioli, 1999 | Gymnotus sylvius | 35453 |
| Gymnotus tigre Albert & Crampton, 2003 | Gymnotus tigre | 49716 |
| Gymnotus tiquie Maxime, Lima & Albert, 2011 | Gymnotus tiquie | 83328 |
| Gymnotus tremulus Houttuyn, 1764 | Electrophorus electricus | 36692 |
| Gymnotus ucamara Crampton, Lovejoy & Albert, 2003 | Gymnotus ucamara | 49730 |
| Gymnotus varzea Crampton, Thorsen & Albert, 2005 | Gymnotus varzea | 55508 |