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

<==o Cottus Linnaeus, 1758; R. As. Mioc. NZ. L. Olig. R. Eu. Mioc. Plioc. R. NA. (sculpins; kivisimput) [N: 34] [FB: 45]
   |-- †C. brevis
   |-- C. aleuticus Gilbert, 1896 (Coastrange sculpin)
   |-- C. amblystomopsis Schmidt, 1904 (Sakhalin sculpin)
   |-- C. asper Richardson, 1836 (Prickly sculpin)
   |-- C. asperrimus Rutter, 1908 (Rough sculpin)
   |--o C. bairdii -group
   |  |-- C. baileyi Robins, 1961 (Black sculpin)
   |  |--+-- C. caeruleomentum Kinziger, Raesly & Neely, 2000 (Blue Ridge sculpin)
   |  |  `--o C. bairdii Girard, 1850 (Mottled sculpin)
   |  |     |-- C. b. bairdii Girard, 1850
   |  |     |-- C. b. punctulatus
   |  |     |-- C. b. semiscaber
   |  |     `-- C. b. kumlieni
   |  |-- C. cognatus Richardson, 1836 (Slimy sculpin)
   |  |-- C. hypselurus Robins & Robison, 1985 (Ozark sculpin)
   |  `-- C. paulus Williams, 2000 (Pygmy sculpin)
   |-- C. beldingii Eigenmann & Eigenmann, 1891 (Paiute sculpin)
   |--o C. carolinae -group
   |  `-- C. carolinae (Gill, 1861) (Banded sculpin)
   |-- C. confusus Bailey & Bond, 1963 (Shorthead sculpin)
   |-- C. czerskii Berg, 1913 (Cherskii's sculpin)
   |-- C. echinatus Bailey & Bond, 1963 (Utah Lake sculpin)
   |-- C. extensus Bailey & Bond, 1963 (Bear Lake sculpin)
   |-- C. ferrugineus Heckel & Kner, 1858
   |-- C. girardi Robins, 1961 (Potomac sculpin)
   |--o C. gobio Linnaeus, 1758 (kivisimppu; Bullhead)
   |  |-- C. g. gobio Linnaeus, 1758 (kivisimppu; Bullhead)
   |  `-- C. g. jaxartensis Berg, 1916
   |-- C. greenei (Gilbert & Culver, 1898) (Shoshone sculpin)
   |-- C. gulosus (Girard, 1854) (Riffle sculpin)
   |-- C. hangiongensis Mori, 1930
   |-- C. kaganowskii Berg, 1932 (Anadyr sculpin)
   |-- C. kazika Jordan & Starks, 1904
   |--o C. kesslerii Dybowski, 1874 (Kessler's sculpin)
   |  |-- C. k. bauntovi Taliev, 1946 (Baunt sand sculpin)
   |  `-- C. k. kesslerii Dybowski, 1874 (Kessler's sculpin)
   |--o C. klamathensis Gilbert, 1898 (Marbled sculpin)
   |  |-- C. k. polyporus
   |  `--+-- C. k. macrops
   |     `-- C. k. klamathensis Gilbert, 1898
   |-- C. leiopomus Gilbert & Evermann, 1894 (Wood River sculpin)
   |-- C. marginatus (Bean, 1881) (Margined sculpin)
   |-- C. nasalis Berg, 1933 (Tubenose sculpin)
   |-- C. nozawae Snyder, 1911
   |-- C. perplexus Gilbert & Evermann, 1894 (Reticulate sculpin)
   |-- C. petiti Bacescu & Bacescu-Mester, 1964
   |-- C. pitensis Bailey & Bond, 1963 (Pit sculpin)
   |--o C. poecilopus Heckel, 1837 (kirjoeväsimppu; Alpine bullhead)
   |  |-- C. p. poecilopus Heckel, 1837 (Alpine bullhead)
   |  `-- C. p. volki (Taranetz, 1933)
   |-- C. pollux Günther, 1873 (Japanese fluvial sculpin)
   |-- C. princeps Gilbert, 1898 (Klamath Lake sculpin)
   |-- C. reinii Hilgendorf, 1879
   |-- C. rhotheus (Smith, 1882) (Torrent sculpin)
   |-- C. ricei (Nelson, 1876) (Spoonhead sculpin)
   |-- C. sibiricus Kessler, 1899 (Siberian sculpin)
   |-- C. spinulosus Kessler, 1872 (Turkestan sculpin)
   |-- C. tenuis (Evermann & Meek, 1898) (Slender sculpin)
   |-- C. hubbsi
   |-- C. bendirei
   `-- C. paulus

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