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

<==o Sciurini Fischer de Waldheim, 1817 [taxonomic history] (squirrels; oravat)
   |?-o †Protosciurus Black, 1963; L.Olig.-L.Mioc. NA.
   |  |-- †P. gondoni
   |  `-- †P. rachelae Black, 1963
   |?- †Freudenthalia Cuesca Bescós, 1988; L.Mioc. Eu.
   |-- Rheithrosciurus macrotis Gray, 1867 [Rhithrosciurus Lydekker, 1891] (Bornean tassel-eared squirrel; töyhtöorava, tupsukorvaorava)
   |-- Sciurillus pusillus Moore, 1959 (Neotropical pygmy squirrel; amazoninkääpiöorava) [Sciurillina Moore, 1959]
   `--o Sciurina Fischer de Waldheim, 1817 [taxonomic history]
      |-- †Douglassciurus jeffersoni (Douglass, 1901) Emry & Korth, 1996 [taxonomic history]
      |-- †Protoscuirus mengi
      |?-o †Miosciurus Black, 1963; L.Mioc. NA.
      |  `-- †M. ballovianus (Cope) [Sciurus ballovianus Cope]
      |-- Syntheosciurus brochus [sgen. => Sciurus??] (panamanvuoriorava)
      |--o Microsciurus J.A. Allen, 1895 [incl. Leptosciurus Allen, 1915; Simosciurus Allen, 1915] (American dwarf squirrels)
      |  |-- M. alfari (central American dwarf Squirrel)
      |  |-- M. mimulus (western dwarf squirrel)
      |  |-- M. flaviventer (amazon dwarf squirrel)
      |  `-- M. santanderensis (colombian dwarf squirrel)
      `--o Sciurus Linnaeus, 1758; L.Mioc. Pleist.-R. NA., Plioc.-R. Eu., R. As. [taxonomic history] (Tree squirrels, gray squirrels, fox squirrel, European red squirrel; oravat)
         |-- †S. olsoni Emry, Korth & Bell, 2005
         |-- (Tenes) anomalus (persianorava)
         |--o (Sciurus) Linnaeus, 1758
         |  |-- S. (S.) vulgaris (European red squirrel; orava)
         |  |-- S. (S.) lis (japaninorava)
         |  |-- S. (S.) carolinensis (gray squirrel; harmaaorava)
         |  |-- S. (S.) aureogaster (mexican gray squirrel)
         |  |-- S. (S.) colliaei (collie's squirrel)
         |  |-- S. (S.) yucatanensis (yucatan squirrel)
         |  |-- S. (S.) variegatoides (variegated squirrel)
         |  |-- S. (S.) deppei (deppe's squirrel)
         |  |--o S. (S.) niger (Fox squirrel; kettuorava)
         |  |  |-- S. (S.) n. niger (kettuorava)
         |  |  |-- S. (S.) n. cinereus (delmarvankettuorava)
         |  |  |-- S. (S.) n. shermani
         |  |  |-- S. (S.) n. vulpinus
         |  |  `-- S. (S.) n. avicennia
         |  |-- S. (S.) oculatus (peter's squirrel)
         |  |-- S. (S.) alleni (allen's squirrel)
         |  |-- S. (S.) nayaritensis (nayarit squirrel or Mexican fox squirrel)
         |  `-- S. (S.) arizonensis (arizonanharmaaorava)
         |-- (Hesperosciurus) griseus (western gray squirrel)
         |--o (Otosciurus) aberti (abertinorava)
         |  |--  S. (O.) a. aberti
         |  `--  S. (O.) a. kaibabensis
         |--o (Guerlinguetus) Gray, 1821
         |  |-- S. (G.) granatensis (red-tailed squirrel)
         |  |-- S. (G.) richmondi (richmond's squirrel)
         |  |-- S. (G.) aestuans (guianan squirrel)
         |  |-- S. (G.) gilvigularis (brazilian squirrel)
         |  |-- S. (G.) ignitus (bolivian squirrel)
         |  |-- S. (G.) pucheranii (colombian squirrel)
         |  |-- S. (G.) stramineus (guayaquil squirrel)
         |  `-- S. (G.) sanborni (sanborn's squirrel)
         |--o (Hadrosciurus) Allen, 1915
         |  |-- S. (H.) flammifer (venezuelan squirrel)
         |  `-- S. (H.) pyrrhinus (junin red squirrel)
         `--o (Uroscuirus) Allen, 1915
            |-- S. (U.) igniventris (northern Amazon red squirrel)
            `-- S. (U.) spadiceus (southern Amazon red squirrel)

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