After Froese & Pauly, 2001 [“The FishBase”]

<==o Cynoglossus [Arelia] Mioc. Eu. R. Oc. ()? [N: 50] [FB: 53]
   |-- C. abbreviatus (Gray, 1834) (Three-lined tongue sole)
   |-- C. acaudatus Gilchrist, 1906 (Natal tongue-fish)
   |-- C. acutirostris Norman, 1939 (Sharpnose tonguesole)
   |-- C. arel (Bloch & Schneider, 1801) (Largescale tonguesole)
   |-- C. attenuatus Gilchrist, 1904 (Fourline tonguesole)
   |-- C. bilineatus (Lacépède, 1802) (Fourlined tonguesole)
   |-- C. borneensis (Bleeker, 1858) (Macau sole)
   |-- C. broadhursti Waite, 1905 (Southern tongue sole)
   |-- C. browni Chabanaud, 1949 (Nigerian tonguesole)
   |-- C. cadenati Chabanaud, 1947 (Ghanian tonguesole)
   |-- C. canariensis Steindachner, 1882 (Canary tonguesole)
   |-- C. capensis (Kaup, 1858) (Sand tonguefish)
   |-- C. carpenteri Alcock, 1889 (Hooked tonguesole)
   |-- C. cynoglossus (Hamilton, 1822) (Bengal tongue sole)
   |-- C. dispar Day, 1877 (Roundhead toungesole)
   |-- C. dollfusi (Chabanaud, 1931)
   |-- C. dubius Day, 1873 (Carrot tonguesole)
   |-- C. durbanensis Regan, 1921 (Durban tonguesole)
   |-- C. feldmanni (Bleeker, 1853) (River tonguesole)
   |-- C. gilchristi Regan, 1920 (Ripplefin tonguesole)
   |-- C. gracilis Günther, 1873
   |-- C. heterolepis Weber, 1910 (Freshwater tongue sole)
   |-- C. interruptus Günther, 1880 (Genko sole)
   |-- C. itinus (Snyder, 1909)
   |-- C. joyneri Günther, 1878 (Red tonguesole)
   |-- C. kapuasensis Fowler, 1905
   |-- C. kopsii (Bleeker, 1851) (Shortheaded tonguesole)
   |-- C. lachneri Menon, 1977 (Lachner's tonguesole)
   |-- C. lida (Bleeker, 1851) (Roughscale tonguesole)
   |-- C. lingua Hamilton, 1822 (Long tongue sole)
   |-- C. macrophthalmus Norman, 1926 (Big-eyed tongue-sole)
   |-- C. macrostomus Norman, 1928 (Malabar tonguesole)
   |-- C. maculipinnis Rendahl, 1921
   |-- C. marleyi Regan, 1921 (Threeline tonguesole)
   |-- C. melampetalus (Richardson, 1846)
   |-- C. microlepis (Bleeker, 1951) (Smallscale tonguesole)
   |-- C. monodi Chabanaud, 1949 (Guinean tonguesole)
   |-- C. monopus (Bleeker, 1849)
   |-- C. ogilbyi Norman, 1926
   |-- C. oligolepis (Bleeker, 1854)
   |-- C. potti Steindachner, 1902
   |-- C. puncticeps (Richardson, 1846) (Speckled tonguesole)
   |-- C. robustus Günther, 1873
   |-- C. sealarki Regan, 1908
   |-- C. semifasciatus Day, 1877 (Bengal tongue-sole)
   |-- C. semilaevis Günther, 1873 (Tongue sole)
   |-- C. senegalensis (Kaup, 1858) (Senegalese tonguesole)
   |-- C. sinicus Wu, 1932
   |-- C. sinusarabici (Chabanaud, 1931)
   |-- C. suyeni Fowler, 1934
   |-- C. trigrammus Günther, 1862
   |-- C. waandersi (Bleeker, 1854)
   `-- C. zanzibarensis Norman, 1939 (Zanzibar tonguesole)

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