n = 58
| Scientific Name | Author | Valid Name | Family | English Name |
|---|---|---|---|---|
| Simpsonichthys adornatus | Costa, 2000 | Hypsolebias adornatus | Rivulidae | |
| Simpsonichthys alternatus | (Costa & Brasil, 1994) | Simpsonichthys alternatus | Rivulidae | |
| Simpsonichthys antenori | (Tulipano, 1973) | Hypsolebias antenori | Rivulidae | |
| Simpsonichthys auratus | Costa & Nielsen, 2000 | Hypsolebias auratus | Rivulidae | |
| Simpsonichthys boitonei | Carvalho, 1959 | Simpsonichthys boitonei | Rivulidae | Lyrefin pearlfish |
| Simpsonichthys bokermanni | (Carvalho & da Cruz, 1987) | Simpsonichthys bokermanni | Rivulidae | |
| Simpsonichthys brunoi | Costa, 2003 | Hypsolebias brunoi | Rivulidae | |
| Simpsonichthys carlettoi | Costa & Nielsen, 2004 | Hypsolebias carlettoi | Rivulidae | |
| Simpsonichthys chacoensis | (Amato, 1986) | Spectrolebias chacoensis | Rivulidae | |
| Simpsonichthys cholopteryx | Costa, Moreira & Lima, 2003 | Simpsonichthys cholopteryx | Rivulidae | |
| Simpsonichthys constanciae | (Myers, 1942) | Simpsonichthys constanciae | Rivulidae | Featherfin pearlfish |
| Simpsonichthys costai | (Lazara, 1991) | Spectrolebias costai | Rivulidae | |
| Simpsonichthys delucai | Costa, 2003 | Simpsonichthys delucai | Rivulidae | |
| Simpsonichthys espinhacensis | Nielsen, Pessali & Dutra, 2017 | Genus Species | New species | |
| Simpsonichthys fasciatus | Costa & Brasil, 2006 | Simpsonichthys fasciatus | Rivulidae | |
| Simpsonichthys filamentosus | Costa, Barrera & Sarmiento, 1997 | Spectrolebias filamentosus | Rivulidae | |
| Simpsonichthys flagellatus | Costa, 2003 | Hypsolebias flagellatus | Rivulidae | |
| Simpsonichthys flammeus | (Costa, 1989) | Hypsolebias flammeus | Rivulidae | |
| Simpsonichthys flavicaudatus | (Costa & Brasil, 1990) | Hypsolebias flavicaudatus | Rivulidae | |
| Simpsonichthys fulminantis | (Costa & Brasil, 1993) | Hypsolebias fulminantis | Rivulidae | |
| Simpsonichthys ghisolfii | Costa, Cyrino & Nielsen, 1996 | Hypsolebias ghisolfii | Rivulidae | |
| Simpsonichthys gibberatus | Costa & Brasil, 2006 | Simpsonichthys gibberatus | Rivulidae | |
| Simpsonichthys harmonicus | Costa, 2010 | Hypsolebias harmonicus | Rivulidae | |
| Simpsonichthys hellneri | (Berkenkamp, 1993) | Hypsolebias hellneri | Rivulidae | |
| Simpsonichthys igneus | Costa, 2000 | Hypsolebias igneus | Rivulidae | |
| Simpsonichthys ilheusensis | Costa & Lima, 2010 | Ophthalmolebias ilheusensis | Rivulidae | |
| Simpsonichthys inaequipinnatus | Costa & Brasil, 2008 | Spectrolebias inaequipinnatus | Rivulidae | |
| Simpsonichthys izecksohni | (Da Cruz, 1983) | Xenurolebias izecksohni | Rivulidae | |
| Simpsonichthys janaubensis | Costa, 2006 | Hypsolebias janaubensis | Rivulidae | |
| Simpsonichthys longignatus | Costa, 2008 | Hypsolebias longignatus | Rivulidae | |
| Simpsonichthys lopesi | Nielsen, Shibatta, Suzart & MartÃn, 2010 | Hypsolebias lopesi | Rivulidae | |
| Simpsonichthys macaubensis | Costa & Suzart, 2006 | Hypsolebias macaubensis | Rivulidae | |
| Simpsonichthys magnificus | (Costa & Brasil, 1991) | Hypsolebias magnificus | Rivulidae | |
| Simpsonichthys margaritatus | Costa, 2012 | Simpsonichthys margaritatus | Rivulidae | |
| Simpsonichthys marginatus | Costa & Brasil, 1996 | Hypsolebias marginatus | Rivulidae | |
| Simpsonichthys mediopapillatus | Costa, 2006 | Hypsolebias mediopapillatus | Rivulidae | |
| Simpsonichthys multiradiatus | (Costa & Brasil, 1994) | Simpsonichthys multiradiatus | Rivulidae | |
| Simpsonichthys myersi | (Carvalho, 1971) | Xenurolebias myersi | Rivulidae | |
| Simpsonichthys nielseni | Costa, 2005 | Simpsonichthys nielseni | Rivulidae | |
| Simpsonichthys nigromaculatus | Costa, 2007 | Simpsonichthys nigromaculatus | Rivulidae | |
| Simpsonichthys notatus | (Costa, Lacerda & Brasil, 1990) | Hypsolebias notatus | Rivulidae | |
| Simpsonichthys ocellatus | Costa, Nielsen & de Luca, 2001 | Simpsonichthys ocellatus | Rivulidae | |
| Simpsonichthys parallelus | Costa, 2000 | Simpsonichthys parallelus | Rivulidae | |
| Simpsonichthys perpendicularis | Costa, Nielsen & de Luca, 2001 | Simpsonichthys perpendicularis | Rivulidae | |
| Simpsonichthys picturatus | Costa, 2000 | Hypsolebias picturatus | Rivulidae | |
| Simpsonichthys punctulatus | Costa & Brasil, 2007 | Simpsonichthys punctulatus | Rivulidae | |
| Simpsonichthys radiosus | Costa & Brasil, 2004 | Hypsolebias radiosus | Rivulidae | |
| Simpsonichthys reticulatus | Costa & Nielsen, 2003 | Spectrolebias reticulatus | Rivulidae | |
| Simpsonichthys rosaceus | Costa, Nielsen & de Luca, 2001 | Simpsonichthys rosaceus | Rivulidae | |
| Simpsonichthys rufus | Costa, Nielsen & de Luca, 2001 | Simpsonichthys rufus | Rivulidae | |
| Simpsonichthys santanae | (Shibatta & Garavello, 1992) | Simpsonichthys santanae | Rivulidae | |
| Simpsonichthys semiocellatus | (Costa & Nielsen, 1997) | Spectrolebias semiocellatus | Rivulidae | |
| Simpsonichthys similis | Costa & Hellner, 1999 | Simpsonichthys similis | Rivulidae | |
| Simpsonichthys stellatus | (Costa & Brasil, 1994) | Simpsonichthys stellatus | Rivulidae | |
| Simpsonichthys suzarti | Costa, 2004 | Simpsonichthys suzarti | Rivulidae | |
| Simpsonichthys trilineatus | (Costa & Brasil, 1994) | Simpsonichthys trilineatus | Rivulidae | |
| Simpsonichthys virgulatus | Costa & Brasil, 2006 | Simpsonichthys virgulatus | Rivulidae | |
| Simpsonichthys zonatus | (Costa & Brasil, 1990) | Simpsonichthys zonatus | Rivulidae |