After Albert & Crampton, 2005, with Recent species from Froese & Pauly, 2001 [“The Fishbase”] and Loureiro & Silva, 2006

<==o Hypopomidae [N: 4/12] [FB: 6/15]
   |-- Hypopomus artedi (Kaup, 1856) Gill, 1864
   `--+--o Brachyhypopomus Mago-Leccia, 1994 (Bluntnose knifefishes) [FB: 6] [A&C: 7+12!]
      |  |-- B. beebei (Schultz, 1944)
      |  |-- B. bombilla Loureiro & Silva, 2006
      |  |-- B. brevirostris (Steindachner, 1868) (Bluntnose knifefish)
      |  |-- B. diazi (Fernández-Yépez, 1972)
      |  |-- B. janeiroensis (Costa & Campos-da-Paz, 1992)
      |  |-- B. jureiae Triques & Khamis, 2003
      |  |-- B. occidentalis (Regan, 1914)
      |  |-- B. pinnicaudatus (Hopkins, 1991)
      |  `== + 11 undescribed species (Albert & Crapton, 2005)
      |--+-- Racenisia fimbriipinna Mago-Leccia, 1994
      |  `-- Microsternarchus bilineatus Fernández-Yépez, 1968
      `--+--o Hypopygus Hoedeman, 1962
         |  |-- H. sp. [Albert & Crampton, 2005]
         |  |-- H. lepturus Hoedeman, 1962
         |  `-- H. neblinae Mago-Leccia, 1994
         `--+-- Stegostenopos cryptogenes Triques, 1997
            `--o Steatogenys Boulenger, 1898
               |-- S. duidae (La Monte, 1929)
               |-- S. elegans (Steindachner, 1880) (Barred knifefish)
               |-- S. ocellatus
               `?- S. mirabilis Steindachner, 1878 [not recognized by Albert & Crampton]

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