After Shoshoni & Tassy (eds.), 1996 and Lister & Sher, 2001

<==o †Mammuthus Burnett, 1830 (mammuts; mammutit)
   |-- †M. subplanifrons (Osborn, 1928)
   `--+-- †M. africanavus (Arambourg, 1952)
      `--+?- †M. lamarmorae (Sardinian mammut; sardinianmammutti)
         `--o †M. meridionalis (Nesti, 1825 [paraphyletic root-mammut]
            |?- †M. creticus (Crete dwarf-mammut; kreetankääpiömammutti)
            |-- †M. meridionalis tamanensis [M. meridionalis Laiatico-stage]
            `--+-- †M. meridionalis voigtstedtensis [M. meridionalis Montevarchi-stage]
               `--+-- †M. trogontherii
                  |?-+--o †M. imperator (emperor mammut; keisarimammutti)
                  |  |  |-- †M. i. ?jeffersoni
                  |  |  `-- †M. i. ?imperator
                  |  `--o †M. columbi (Colombian mammut; amerikanmammutti)
                  |     |?- †M. c. columbi
                  |     `?- †M. c. exilis (kaliforniankääpiömammutti)
                  `--+-- †M. meridionalis [Bacton-stage]
                     `--+-- †M. armeniacus
                        `--+-- †M. hayi
                           `--+-- †M. fraasi
                              `--o †M. primigenius (Blumenbach, 1799) (woolly mammut, mammutti, villakarvamammutti)
                                 |-- †M. p. sibiricus (Russian mammut; venäjänmammutti
                                 `--+-- †M. p. wrangeliensis (Wrangel Island mammut; wrangelinsaartenmammutti) [died out only 4000 years ago!]
                                    |-- †M. p. primigenius (woolly mammut, European mammut; euroopanmammutti, villakarvamammutti)
                                    `--+-- †M. p. alaskensis (Alaskan mammut; alaskanmammutti)
                                       `-- †M. p. compressus (Great Lakes mammut; suurtenjärvienmammutti)

Note:

Taxonomy of genus Mammuthus is murky, partly because of great deal of fossils available. These fossils and studies made of them show that Eurasian mammut-species [Mammuthus meridionalis, Mammuthus trogontherii and Mammuthus primigenius] form a single slowly evolving lineage, in which form-separation is difficult or impossible.

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