After McKenna & Bell, 1997, with Recent species from Nowak, 1991

<==o Castorinae Hemprich, 1820 (beavers; aitomajavat)
   |?-o †Agnotocastor Stirton, 1935; L.-U.Olig. As. L.Olig. NA.
   |  |-- †A. coloradensis R.W. Wilson, 1949
   |  |-- †A. galushai Emry, 1972
   |  |-- †A. montanus (Scott, 1893) [Steneofiber montanus Scott, 1893; Agnotocastor montanus (Scott); Stirton, 1935, and A.E. Wood, 1937]
   |  |-- †A. praetereadens Stirton, 1935
   |  `-- †A. readingi Korth, 1988
   `--+-- †Migmacastor procumbodens Korth & Rybczynski, 2003
      `--+--o †Capacikalini L.D. Martin, 1987
         |  |--o †Capacikala Macdonald, 1963; U.Olig.-L.Mioc. NA., L.Mioc. As.
         |  |  |-- †C. gradatus (Cope, 1878) [Steneofiber gradatus Cope, 1878; Palaeocastor gradatus (Cope); Stirton, 1935; Capacikala gradatus (Cope) Macdonald, 1963, Macdonald, 1970, Fremd et al., 1994, and Xu, 1996]
         |  |  `-- †C. parvus Xu, 1996
         |  `?-o †Pseudopalaeocastor L.D. Martin, 1987; L.Mioc. NA.
         |     |-- †P. osmagnus (Xu, 1999) [taxonomic history]
         |     `-- †P. barbouri (Peterson, 1905) [taxonomic history]
         `--o Castorini Hemprich, 1820 (nykymajavat)
            |--o †Euhapsina L.D. Martin, 1987
            |  |--o †Fossorcastor L.D. Martin, 1987; L.Mioc. NA.
            |  |  |-- †F. brachyceps (Matthew, 1907) L.D. Martin, 1987 [taxonomic history]
            |  |  `-- †F. fossor (Peterson, 1905) [taxonomic history]
            |  `--o †Euhapsis Peterson, 1905; L.Mioc. NA.
            |     |-- †E. breugerorum L.D. Martin, 1987
            |     |-- †E. ellicottae L.D. Martin, 1987
            |     |-- †E. luskensis Xu, 1996
            |     `-- †E. platyceps Peterson, 1905
            `--o Castorina Hemprich, 1820 (nykymajavat)
               |--o †Propalaeocastor Borisoglebskaya, 1967; L.-U.Olig. As.
               |  |-- †P. butselensis
               |  |-- †P. irtyshensis
               |  |-- †P. kazachstanicus
               |  |-- †P. shevyrevae
               |  `-- †P. zaissanensis
               `--+-- †Palaeomys Kaup, 1832 [Chelodus Kaup, 1832; Chelodon Gloger, 1841 (unjust. emend.); Chaelodus Agassiz, 1842 (lapsus calami)] [incl.? †Chalicomys Kaup, 1832, non Chalicomys Schlosser, 1924 (lapsus calami)] [synonomous status of Palaeomys/Chalicomys is unclear (Korth, 2001)]; U.Olig.-U.Mioc. Eu., M.-U.Olig. As.
                  `--+--o †Palaeocastor Leidy, 1869 [taxonomic history] U.Olig.-U.Mioc. Eu., M.-U.Mioc. As.
                     |  |-- †P. nebrascensis (Leidy, 1856) [taxonomic history]
                     |  |-- †P. peninsulatus (Cope, 1881) [taxonomic history]
                     |  `--o (Capatanka) Macdonald, 1963
                     |     |-- †P. (C.) cankpeopi (MacDonald, 1963) [taxonomic history]
                     |     `-- †P. (C.) gaulodon (Matthew, 1907) [taxonomic history]
                     `--+?-o †Hystricops Leidy, 1856 [taxonomic history] ?M.Mioc. As. M.-U. Mioc. As. [treated as Castoroidine by Korth (2017)]
                        |  |-- †H. browni Shotwell, 1963
                        |  `-- †H. venustus (Leidy, 1858) [taxonomic history]
                        `--o Castor Linnaeus, 1758 [Fiber Dumeril, 1806 non Fiber G. Cuvier, 1800 (Ondatra)]; Mamcastorus Herrera, 1899] [incl. Sinocastor Young, 1934] U.Mioc.-R. As. Eu. NA. (beavers; majavat)
                           |?- †C. zdanskyi
                           |--o C. fiber Linnaeus, 1758 (Eurasian beaver; majava, euroopanmajava) [8 ssp.]
                           |  |-- C. f. fiber (majava; beaver) [Fennoscandia]
                           |  |-- C. f. albicus (länsimajava)
                           |  |-- C. f. vistulanus
                           |  |-- C. f. biellorussieus
                           |  |-- C. f. birulai
                           |  |-- C. f. pohlei
                           |  |-- C. f. tuvinicus
                           |  `-- C. f. orientoeuropeas
                           |-- †C. andersoni
                           |-- †C. californicus (kalifornianmajava)
                           `--o C. canadensis Kuhn, 1820 (North American beaver; kanadanmajava) [number and validity of subspecies suspecious]
                              |-- C. c. acadicus Bailey
                              |-- C. c. baileyi Nelson
                              |-- C. c. belugae Taylor (Cook Inlet beaver)
                              |-- C. c. caecator Bangs (Newfoundland beaver)
                              |-- C. c. canadensis Kuhl (Canadian beaver)
                              |-- C. c. concisor
                              |-- C. c. carolinensis Rhoads (Carolina beaver)
                              |-- C. c. duchesnei
                              |-- C. c. frondator Mearns (Sonora beaver)
                              |-- C. c. idoneus
                              |-- C. c. labradorensis
                              |-- C. c. leucodonta Gray (Pacific beaver)
                              |-- C. c. mexicanus Bailey (Rio Grande beaver)
                              |-- C. c. michiganensis Bailey (Woods beaver)
                              |-- C. c. missouriensis Bailey (Missouri River beaver)
                              |-- C. c. pacificus Rhoads (Washington beaver)
                              |-- C. c. pallidus
                              |-- C. c. phaeus Heller (Admiralty beaver)
                              |-- C. c. rostralis
                              |-- C. c. repentinus Goldman (Sonora beaver)
                              |-- C. c. sagittatus
                              |-- C. c. shastensis Taylor (Shasta beaver)
                              |-- C. c. subauratus (California Golden beaver)
                              |-- C. c. taylori Davis
                              |-- C. c. texensis Bailey (Texas beaver)

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