Some North American Microtus -species after Repenning, 1983

<==o Microtus Schrank, 1798 sensu lato; U.Plioc.-R. As. Eu. NA., R. Af. CA. (voles; myyrät) [taxonomic history]
   |--o Phaiomys [†Allophaiomys Kormos, 1933; Microtus (Phaiomys)]
   |  |?- P. leucurus (lumimyyrä)
   |  |-- P. umbrosus Merriam, 1898 ()? [Microtus umbrosus]
   |  `--o ?†(Allophaiomys) Kormos, 1933
   |     |-- †P. pliocaenicus (Kormos, 1933)
   |     `-- †P. guildayi (van der Maulen, 1978)
   `--+--o Pitymys McMurtie, 1831 [Pedomys Baird, 1858; Herpetomys Merriam, 1898; Microtus (Pitymys) McMurtie, 1831] ()?
      |  |?- †P. henseli
      |  |?- P. ludoviacus
      |  |--+-- †P. cumberlandensis (van der Maulen, 1978)
      |  |  `--+-- P. guatemalensis Merriam, 1898 ()?
      |  |     `-- P. oaxacensis Goodwin, 1966 ()?
      |  `--+-- †P. meadensis (Hibbard, 1944)
      |     `--+-- P. quasiater (Coues, 1874) (Cuidad de Mexicon tunnelimyyrä??)
      |        `--+--+-- †P. llanensis (Hibbard, 1944)
      |           |  `-- P. ochrogaster (Wagner, 1842) (preeriamyyrä)
      |           `--+?- †P. aratai (Martin, 1974)
      |              |?- †P. hibbardi (Holman, 1959)
      |              |-- †P. mcnowni Hibbard, 1937 [+ P. aratai, P. hibbardi, synon. to P. nemoralis?]
      |              `--o P. pinetorum -species-group
      |                 |-- P. pinetorum (Le Conte, 1830) (amerikantunnelimyyrä)
      |                 |-- P. nemoralis  ()?
      |                 `-- P. parvulus ()?
      `--+--+-- †Microtus paroperarius
         |  `-- Microtus oeconomus (lapinmyyrä)
         `-- Microtus Schrank, 1798 sensu stricto?; U.Plioc.-R. As. Eu. NA., R. Af. CA. (voles; myyrät) [taxonomic history]

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