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

<==o Cetopsidae sensu Nelson, 1994 (valasmonnit; Whalelike catfishes) [N: 12 species] [FB: 6/19]
   |-- Bathycetopsis oliveirai Lundberg & Rapp-Py-Daniel, 1994
   |-- Cetopsis coecutiens (Lichtenstein, 1819)
   |--o Denticetopsis [2]
   |  |-- D. royeroi Ferraris, 1996
   |  `-- D. sauli Ferraris, 1996
   |-- Hemicetopsis candiru (Spix & Agassiz, 1829)
   |-- Paracetopsis bleekeri Bleeker, 1862
   `--o Pseudocetopsis [13]
      |-- P. amphiloxa (Eigenmann, 1914)
      |-- P. baudoensis Dahl, 1960
      |-- P. gobioides (Kner, 1858)
      |-- P. jurubidae Fowler, 1944
      |-- P. macilenta (Eigenmann, 1912)
      |-- P. macroteronema (Boulenger, 1898)
      |-- P. minuta (Eigenmann, 1912)
      |-- P. morenoi (Fernández-Yépez, 1972)
      |-- P. motatanensis Schultz, 1944
      |-- P. orinoco Schultz, 1944
      |-- P. othonops (Eigenmann, 1912)
      |-- P. plumbea (Steindachner, 1882)
      `-- P. praecox Ferraris & Brown, 1991

Note:

Nelson (1994) gives count of species in this family as 12. Froese & Pauly (“The Fishbase”; 2001) maintains that this family contains 23 species, but they include genus Helogenes within the family, which has elsewhere given a monotypic family of Helogeneidae (Nelson, 1994).

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