n = 29
| Scientific Name | Author | Valid Name | Family | English Name |
|---|---|---|---|---|
| Nannostomus anduzei | Fernandez & Weitzman, 1987 | Nannostomus anduzei | Lebiasinidae | |
| Nannostomus anomalus | Steindachner, 1876 | Nannostomus beckfordi | Lebiasinidae | Golden pencilfish |
| Nannostomus aripiragensis | Meinken, 1931 | Nannostomus beckfordi | Lebiasinidae | Golden pencilfish |
| Nannostomus aripirangensis | Meinken, 1931 | Nannostomus beckfordi | Lebiasinidae | Golden pencilfish |
| Nannostomus beckfordi | Günther, 1872 | Nannostomus beckfordi | Lebiasinidae | Golden pencilfish |
| Nannostomus beckfordi surinami | Hoedeman, 1954 | Nannostomus beckfordi | Lebiasinidae | Golden pencilfish |
| Nannostomus bifasciatus | Hoedeman, 1954 | Nannostomus bifasciatus | Lebiasinidae | Whiteside pencilfish |
| Nannostomus britskii | Weitzman, 1978 | Nannostomus britskii | Lebiasinidae | Spotstripe pencilfish |
| Nannostomus digrammus | (Fowler, 1913) | Nannostomus digrammus | Lebiasinidae | Twostripe pencilfish |
| Nannostomus eques | Steindachner, 1876 | Nannostomus eques | Lebiasinidae | Brown pencilfish |
| Nannostomus erythrurus | (Eigenmann, 1909) | Nannostomus erythrurus | Lebiasinidae | |
| Nannostomus espei | (Meinken, 1956) | Nannostomus espei | Lebiasinidae | Barred pencilfish |
| Nannostomus grandis | Zarske, 2011 | Nannostomus grandis | Lebiasinidae | |
| Nannostomus harrisoni | (Eigenmann, 1909) | Nannostomus harrisoni | Lebiasinidae | Blackstripe pencilfish |
| Nannostomus lateralis | Boulenger, 1895 | Characidium laterale | Crenuchidae | |
| Nannostomus limatus | Weitzman, 1978 | Nannostomus limatus | Lebiasinidae | Elegant pencilfish |
| Nannostomus marginatus | Eigenmann, 1909 | Nannostomus marginatus | Lebiasinidae | |
| Nannostomus marginatus mortenthaleri | Paepke & Arendt, 2001 | Nannostomus mortenthaleri | Lebiasinidae | |
| Nannostomus marginatus picturatus | Hoedeman, 1954 | Nannostomus marginatus | Lebiasinidae | |
| Nannostomus marilynae | Weitzman & Cobb, 1975 | Nannostomus marilynae | Lebiasinidae | Greenstripe pencilfish |
| Nannostomus marylinae | Weitzman & Cobb, 1975 | Nannostomus marilynae | Lebiasinidae | Greenstripe pencilfish |
| Nannostomus minimus | Eigenmann, 1909 | Nannostomus minimus | Lebiasinidae | Least pencilfish |
| Nannostomus mortenthaleri | Paepke & Arendt, 2001 | Nannostomus mortenthaleri | Lebiasinidae | |
| Nannostomus nigrotaeniatus | Zarske, 2013 | Nannostomus nigrotaeniatus | Lebiasinidae | |
| Nannostomus nitidus | Weitzman, 1978 | Nannostomus nitidus | Lebiasinidae | Shining pencilfish |
| Nannostomus rubrocaudatus | Zarske, 2009 | Nannostomus rubrocaudatus | Lebiasinidae | |
| Nannostomus simplex | Eigenmann, 1909 | Nannostomus beckfordi | Lebiasinidae | Golden pencilfish |
| Nannostomus trifasciatus | Steindachner, 1876 | Nannostomus trifasciatus | Lebiasinidae | Threestripe pencilfish |
| Nannostomus unifasciatus | Steindachner, 1876 | Nannostomus unifasciatus | Lebiasinidae | Oneline pencilfish |