Smiloddon, Hoplophoneus and Koponomos,

Hoplophoneus primaevus (Leidy and Owen 1851, Cope 1874, Late Eocene to Early Oligocene, 30mya, up to 350 pounds in weight est) is a sister to Smilodon in the LRT. Barrett 2016 considered Hoplophoneus a relative of the cat, Nimravus. The LRT does not confirm that hypothesis of interrelationships.

Kolponomos newportensis (Stirton 1960, Tedford, Barnes and Ray 1994, early Miocene) originally considered a bear close to pinnipeds, Kolponomus enters the LRT close to the South American bear, Tremarctos, but closer to Smilodon, the sabertooth. A few postcranial bones are known indicating this taxon was amphibious, but not a strong swimmer. Reports indicate the snout was adapted to prying shellfish off rocky substrates and massive molars were able to crush the shells, like a walrus.

Smilodon populator or fatalis (Lund 1842, Pleistocene to Holocene, 2.5mya to near present) nests with Proailurus in the LRT as a pre-cat and pre-hyaena, attaining the size of a lion by convergence.

Barrett PZ 2016. Taxonomic and systematic revisions to the North American Nimravidae (Mammalia, Carnivora) PeerJ 4:e1658 https://doi.org/10.7717/peerj.1658

Brookes J 1828. Section Carnivora. A catalogue of the Anatomical and Zoological Museum of Joshua Brookes. London: Richard Taylor. p. 16.

Cope ED 1874. Report upon vertebrate fossils discovered in New Mexico, with descriptions of new species. Chief of Engineers Annual Report, Appendix, S. 589-606, U.S. Government Printing Office, Washington.

Erxleben JCP 1777. Systema regni animalis per classes, ordines, genera, species, varietatis cum synonymia et historia animalium. Classes I. Mammalia. Lipsiae.

Hunt RM Jr 2003. Intercontinental Migration of Large Mammalian Carnivores: Earliest Occurrence of the Old World Beardog Amphicyon (Carnivora, Amphicyonidae) in North America. Bulletin of the American Museum of Natural History 279: 77–115.

Kaup JJ 1828. Über Hyaena, Uromastix, Basiliscus, Corthaeolus, Acontias. Isis 21, columns 1144–1150.

Kretzoi M 1938. Die Raubtiere von Gombaszög nebst einer Übersicht der Gesamtfauna. Annales Musei Nationalis Hungarici 31:88–157.

Koufos GD and Konidaris GE 2011. Late Miocene carnivores of the Greco-Iranian Province: Composition, guild structure and palaeoecology. Palaeogeography, Palaeoclimatology, Palaeoecology. 305: 215. doi:10.1016/j.palaeo.2011.03.003

Leidy J and Owen R 1851. Academy of Natural Sciences, Philadelphia Proceedings 239:

Linnaeus C von 1758. Systema naturæ per regna tria naturæ, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata.

Lund PW 1842. Blik paa Brasiliens Dyreverden för sidste Jordomvæltning (in Danish). Copenhagen: Det Kongelige Danske Videnskabernes Selskabs Naturvidenskabelige og Matematiske Afhandlinger. pp. 54–57.

Stirton RA 1960. A Marine Carnivore from the Clallam Miocene Formation, Washington: Its Correlation with Nonmarine Faunas. University of California Publications in Geological Sciences. 36 (7).

Tedford RH, Barnes LG and Ray CE 1994. The early Miocene littoral ursoid carnivoran Kolponomos: Systematics and mode of life (PDF). Proceedings of the San Diego Society of Natural History. 29: 11–32.

Tseng ZJ, Grohé C and Flynn JJ 2016. A unique feeding strategy of the extinct marine mammal Kolponomos: convergence on sabretooths and sea otters. Proceedings of the Royal Society B https://doi.org/10.1098/rspb.2016.0044

wiki/Smilodon
wiki/Hoplophoneus
wiki/Kolponomos

Mammalia

Ornithorhynchus and kin

Marsupials - Metatheria

Eomaia and kin

Monodelphis and kin

Placentalia 2

Scandentia

Tupaia and kin

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Rattus and kin

Placentalia 1