[organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Pisces
     Class Osteichthyes Huxley, 1880 - bony fishes and tetrapods see Clade Osteichthyes Huxley 1880 [Moore & Near 2020]
       Order Osmeriformes Regan, 1913 - freshwater smelts
         Family Microstomatidae Bleeker, 1859 - pencilsmelts
           Genus Nansenia Jordan & Evermann, 1896
             1 Nansenia groenlandica (Reinhardt, 1840) - large-eyed argentine
             2 Nansenia iberica Matallanas, 1985
             3 Nansenia longicauda Kawaguchi & Butler, 1984
             4 Nansenia oblita (Facciolà, 1887)
             5 Nansenia tenera Kawaguchi & Butler, 1984