美洲拟狮最早由美国古生物学家约瑟夫·莱迪于 1853 年以 Felis atrox 为名命名并进行发表[4]。Hemmer 于 1974 年提议将美洲拟狮以三名法命名为 Panthera leo atrox[5],这项提议于 1985 年受到 Björn Kurten(英语:Björn Kurten)的支持[6]。
美洲拟狮一开始被认为是豹亚科下独立物种,学名为 Panthera atrox/ˈpænθərəˈætrɒks/,拉丁文意思是“凶残的豹”。但是一部分的古生物学家认为美洲拟狮应为现存非洲狮及穴狮的近亲,而在之后将美洲拟狮命名为 P. leo atrox,列为非洲狮的亚种而非独立物种[7]。近年来,美洲拟狮与穴狮则再次被视为是独立物种[8]。
Christiansen, P.; Harris, J. M. Craniomandibular morphology and phylogenetic affinities of Panthera atrox: implications for the evolution and paleobiology of the lion lineage. Journal of Vertebrate Paleontology. 2009, 29 (3): 934−945. doi:10.1671/039.029.0314.
Christiansen, P.; Harris, J. M. Body size of Smilodon (Mammalia: Felidae). Journal of Morphology. 2005-10-18, 266 (3): 369–384. PMID 16235255. doi:10.1002/jmor.10384.
Sorkin, B. A biomechanical constraint on body mass in terrestrial mammalian predators. Lethaia. 2008-04-10, 41 (4): 333–347. doi:10.1111/j.1502-3931.2007.00091.x.
Christiansen, Per; Harris, John M. Craniomandibular Morphology and Phylogenetic Affinities of Panthera atrox: Implications for the Evolution and Paleobiology of the Lion Lineage. Journal of Vertebrate Paleontology. 2009, 29 (3): 934–945. doi:10.1671/039.029.0314.
Chimento, N. R.; Agnolin, F. L. The fossil American lion (Panthera atrox) in South America: Palaeobiogeographical implications. Comptes Rendus Palevol. 2017, 16 (8): 850–864. doi:10.1016/j.crpv.2017.06.009.
Seymour, Kevin L. The Felinae (Mammalia: Felidae) from the Late Pleistocene tar seeps at Talara, Peru, with a critical examination of the fossil and recent felines of North and South America (MSc论文). University of Toronto. 1983.
Yamaguchi, N.; Cooper, A.; Werdelin, L.; MacDonald, D. W. Evolution of the mane and group-living in the lion (Panthera leo): A review. Journal of Zoology. 2004, 263 (4): 329. doi:10.1017/S0952836904005242.