After Carroll, 1988, and Nelson, 1994, with Recent species from Froese & Pauly, 2001 [“The Fishbase”]

<==o Synbranchidae [Synbranchoidei] (suoankeriaat) [Nelson: 4/19] [Fishbase: 4/16]
   |-- Macrotrema caligans (Cantor, 1849) [Macrotrematinae]
   `--o Synbranchinae
      |--o Monopterus [Amphipnous (sg.)] [N: 6] [FB: 7]
      |  |-- M. albus (Zouiev, 1793) (Swamp eel)
      |  |-- M. boueti (Pellegrin, 1922) (Liberian swamp eel)
      |  |-- M. cuchia (Hamilton, 1822) (Cuchia)
      |  |-- M. eapeni Talwar, 1991
      |  |-- M. fossorius (Nair, 1951) (Malabar swampeel)
      |  |-- M. indicus (Silas & Dawson, 1961) (Bombay swampeel)
      |  `-- M. roseni Bailey & Gans, 1998
      |--o Ophisternon [Furmastix] [N: 10] [FB: 6]
      |  |-- O. aenigmaticum Rosen & Greenwood, 1976 (Obscure swamp eel)
      |  |-- O. afrum (Boulenger, 1909) (Guinea swamp eel)
      |  |-- O. bengalense McClelland, 1844 (Bengal eel)
      |  |-- O. candidum (Mees, 1962) (Blind cave eel)
      |  |-- O. gutturale (Richardson, 1845) (Australian swamp eel)
      |  `-- O. infernale (Hubbs, 1938) (Blind swamp eel)
      `--o Synbranchus [2]
         |-- S. madeirae Rosen & Rumney, 1972
         `-- S. marmoratus Bloch, 1795 (Marbled swamp eel)

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