[organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Pisces
     Class Osteichthyes Huxley, 1880 - bony fishes see [unranked] Euteleostomi
       Order Osmeriformes - freshwater smelts see Suborder Osmeroidei
         Family Alepocephalidae - slickheads
           Genus Rouleina Jordan, 1923 - Roule's smooth-head
             1 Rouleina attrita (Vaillant, 1888) - softskin smooth-head
             2 Rouleina maderensis Maul, 1948 - Madeiran smooth-head