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

<==o Paralichthyidae (Large-tooth flounders) [N: 16/85] [FB: 14/102]
   |--o Ancylopsetta [4]
   |  |-- A. cycloidea Tyler, 1959 (Cyclope flounder)
   |  |-- A. dendritica Gilbert, 1890 (Three-spot flounder)
   |  |-- A. dilecta (Goode & Bean, 1883) (Three-eye flounder)
   |  `-- A. kumperae Tyler, 1959 (Foureyed flounder)
   |?- Cephalopsetta [not recognized by the FishBase]
   |-- Gastropsetta frontalis Bean, 1895 (Shrimp flounder)
   |--o Hippoglossina [5]
   |  |-- H. bollmani Gilbert, 1890 (Spotted flounder)
   |  |-- H. macrops Steindachner, 1876 (Bigeye flounder)
   |  |-- H. montemaris de Buen, 1961
   |  |-- H. stomata Eigenmann & Eigenmann, 1890 (Bigmouth flounder)
   |  `-- H. tetrophthalma (Gilbert, 1890) (Fourspot flounder)
   |?- Lioglossina [not recognized by the FishBase]
   |-- Paralichthys [Vorator] Mioc. NA. R. Oc. [23]
   |-- Pseudorhombus [26]
   |-- Tarphops elegans Amaoka, 1969
   |-- Tephrinectes sinensis (Lacépède, 1802)
   |-- Thysanopsetta naresi Günther, 1880
   |-- Verecundum rasile Jordan, 1891
   |-- Xystreurys liolepis Jordan & Gilbert, 1880 (Fantail flounder)
   `--o Cyclopsetta -group
      |--o Citharichthys [17]
      |  |-- C. arctifrons Goode, 1880 (Gulf Stream flounder)
      |  |-- C. arenaceus Evermann & Marsh, 1900 (Sand whiff)
      |  |-- C. cornutus (Günther, 1880) (Horned whiff)
      |  |-- C. dinoceros Goode & Bean, 1886
      |  |-- C. fragilis Gilbert, 1890 (Gulf sanddab)
      |  |-- C. gilberti Jenkins & Evermann, 1889 (Bigmouth sanddab)
      |  |-- C. gordae Beebe & Tee-Van, 1938 (Mimic sandab)
      |  |-- C. gymnorhinus Gutherz & Blackman, 1970 (Anglefin whiff)
      |  |-- C. macrops Dresel, 1885 (Spotted whiff
      |  |-- C. mariajorisae van der Heiden & Mussot-Pérez, 1995
      |  |-- C. platophrys Gilbert, 1891 (Small sandab)
      |  |-- C. sordidus (Girard, 1854) (Pacific sanddab)
      |  |-- C. spilopterus Günther, 1862 (Bay whiff)
      |  |-- C. stampflii (Steindachner, 1894) (Smooth flounder)
      |  |-- C. stigmaeus Jordan & Gilbert, 1882 (Speckled sanddab)
      |  |-- C. valdezi Cervigón, 1986
      |  `-- C. xanthostigma Gilbert, 1890 (Longfin sanddab)
      |--o Cyclopsetta [4]
      |  |-- C. chittendeni Bean, 1895 (Mexican flounder)
      |  |-- C. fimbriata (Goode & Bean, 1885) (Spotfin flounder)
      |  |-- C. panamensis (Steindachner, 1876) (God's flounder)
      |  `-- C. querna (Jordan & Bollman, 1890) (Toothed flounder)
      |--o Etropus [9]
      |  |-- E. ciadi van der Heiden & Plascencia Gonzáles, 2005
      |  |-- E. crossotus Jordan & Gilbert, 1882 [incl. Etropus intermedius Norman, 1933] (Fringed flounder)
      |  |-- E. cyclosquamus Leslie & Stewart, 1986
      |  |--o E. delsmani Chabanaud, 1940
      |  |  |-- E. d. delsmani Chabanaud, 1940
      |  |  `-- E. d. pacificus Nielsen, 1963 (Delsman's flounder)
      |  |-- E. ectenes Jordan, in Jourdan & Goss, 1889 (Sole flounder)
      |  |-- E. longimanus Norman, 1933
      |  |-- E. microstomus (Gill, 1864) (Smallmouth flounder)
      |  |-- E. peruvianus Hildebrand, 1946 (Peruvian flounder)
      |  `-- E. rimosus Goode & Bean, 1885 (Gray flounder)
      `--o Syacium [8]
         |-- S. guineensis (Bleeker, 1862)
         |-- S. gunteri Ginsburg, 1933 (Shoal flounder)
         |-- S. latifrons (Jordan & Gilbert, 1882) (Beach flounder)
         |-- S. longidorsale Murakami & Amaoka, 1992 (Longfin flounder)
         |-- S. maculiferum (Garman, 1899) (Clearspot flounder)
         |-- S. micrurum Ranzani, 1842 (Channel flounder)
         |-- S. ovale (Günther, 1864) (Oval flounder)
         `-- S. papillosum (Linnaeus, 1758) (Dusky flounder)

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