Nimravides

This article is about the extinct saber-toothed cat Nimravides. For the similarly named "false" saber-toothed cat, see Nimravus.

Nimravides Temporal range: Late Miocene PreꞒ Ꞓ O S D C P T J K Pg N
Nimravides catocopis skull
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Carnivora
Suborder:	Feliformia
Family:	Felidae
Subfamily:	† Machairodontinae
Tribe:	† Homotherini
Genus:	† Nimravides Kitts 1958
Type species
Nimravides thinobates (Macdonald, 1948)
Other Species
N. catocopis(Cope, 1887) N. pedionomus(MacDonald, 1948) N. hibbardi(Dalquest, 1969) N. galianiBaskin, 1981
Synonyms
N. catocopis Machaerodus catacopsisCope, 1887 Machairodus catacopsis Nimravides catacopsis Nimravides catocopsis(misspelling) N. thinobates Pseudaelurus thinobatesMacDonald, 1948 N. pedionomus Pseudaelurus pedionomus N. hibbardi Pseudaelurus hibbardi

Nimravides is a genus of extinct saber-toothed cats that lived in North America during the Late Miocene, between 11 and 6.5 Ma. ^[1] Despite its scientific name, Nimravides does not belong to the Nimravidae, but is a true cat belonging to the family Felidae. ^[2]

History and taxonomy

The genus Nimravides was originally described by Kitt in 1958 for the species "Pseudaelurus" thinobates. ^[3] In 1969, Dalquest described the species Pseudaelurus hibbardi. ^[4] The species Machaerodus catocopis was described by Cope in 1887, based on a partial mandible from the Loup Fork Beds. ^[5] The species Pseudaelurus thinobates and Pseudaelurus pedionomus were both described by James Reid MacDonald in 1948. ^{[6] [7]}

In 1975, Martin and Schultz reassigned Machairodus catacopsis to Nimravides and suggested that N. thinobates was a junior synonym of the former species. ^[8] The species N. galiani was first described in 1981 based on fragmentary material from the Love Bone Beds in Florida. The same paper also described additional fossils of N. thinobates compared to the holotype of N. catacopsis, and concluded that N. catacopsis was best considered a nomen vanum and the material assigned to it should be considered N. thinobates. ^[9]

"Pseudaelurus" pedionomus was reassigned to Nimravides in 1990 by Beaumont. ^[10] In 2003, Tom Rothwell reassigned Pseudaelurus hibbardi to Nimravides. ^[11] And in 2010 it was suggested that N. hibbardi was a junior synonym of Adelphailurus kansensis. ^[12] In 2013, Mauricio Anton et al. suggested that N. catacopsis should be re-reassigned back to Machairodus. ^[13] But this was refuted in 2022 by Jiangzuo et al.. ^[1]

Description

Nimravides catacopsis, one of the largest and latest species, was quite large, measuring 100 cm (1.0 m) at the shoulder and was similar in size to a large tiger. It was also possessed of long, powerful legs and a long back. For many decades, it was also believed to be a member of the genus Machairodus , but, despite the similarities between them at first glance, based on autapomorphies in the skeleton, the two animals are too different to be classified as species of the same genus, and thus, Nimravides remains separate as its own genus within the Homotherini. ^[14]

Paleobiology and paleoecology

Evidence published in November, 2022 suggests Nimravides was endemic to North America and that when the Machairodus- Amphimachairodus lineage emigrated to North America from Eurasia, differing aspects of their cranial anatomy allowed the newly arrived machairodont genera to survive a faunal change occurring during the early-late Hemphillian stage of the Miocene Epoch some 6.5 million years ago. The analysis also determined that the Machairodus-Amphimachairodus lineage did not have a competitive edge over Nimravides, implying that neither newcomer or endemic species were superior to one another in regards to hunting adaptations. ^[1]

References

1. Jiangzuo, Qigao; Li, Shijie; Deng, Tao (2022). "Parallelism and lineage replacement of the late Miocene scimitar-toothed cats from the old and New World" (PDF). iScience. 25 (12): 105637. Bibcode:2022iSci...25j5637J. doi:10.1016/j.isci.2022.105637. PMC   9730133 . PMID   36505925.
2. Larry D.Martin (1998). Felidae in Evolution of Tertiary Mammals of North America, Volume 1: Terrestrial Carnivores, Ungulates, Ungulatelike Mammals. Cambridge University Press.
3. Kitts, David B. (1958). "Nimravides, a New Genus of Felidae from the Pliocene of California, Texas and Oklahoma". Journal of Mammalogy. 39 (3): 368–375. doi:10.2307/1376145. JSTOR   1376145.
4. Dalquest, W. W. (1969). "Pliocene carnivores of the Coffee Ranch (type Hemphill) local fauna" (PDF). Bulletin of the Texas Memorial Museum. 15: 1–44.
5. Cope, Edward Drinker (1887). "A saber-tooth tiger from the Loup Fork Beds". The American Naturalist. 21 (11): 1019–1020.
6. MacDonald, James Reid (1948). "The Pliocene carnivores of the Black Hawk Ranch". University of California Publications, Bulletin of the Department of Geological Sciences. 28: 53–80.
7. MacDonald, James Reid (1948). "A new species of Pseudaelurus from the lower Pliocene of Nebraska". University of California Publications, Bulletin of the Department of Geological Sciences. 28: 45–52.
8. Martin, Larry D.; Schultz, C. Bertrand (1975). "Scimitar-toothed Cats, Machairodus and Nimravides, from the Pliocene of Kansas and Nebraska". Bulletin of the University of Nebraska State Museum. 10.
9. Baskin, Jon A. (1981). "Barbourofelis (Nimravidae) and Nimravides (Felidae), with a Description of Two New Species from the Late Miocene of Florida". Journal of Mammalogy. 62 (1): 122–139. doi:10.2307/1380483. JSTOR   1380483.
10. Beaumont, G. (1990). "Contribution à l'étude du genre Nimravides Kitts (Mammalia, Carnivora, Felidae). L'espèce N. pedionomus (Macdonald)" [Contribution to the study of the genus Nimravides Kitts (Mammalia, Carnivora, Felidae). The species N. pedionomus (Macdonald)]. Archives des Sciences, Genève (in French). 43 (1): 125–157. doi:10.5169/seals-740122.
11. Rothwell, Tom (2003). "Phylogentic systematics of North American Pseudaelurus (Carnivora: Felidae)". American Museum Novitates (3403): 1–64. doi:10.1206/0003-0082(2003)403<0001:PSONAP>2.0.CO;2. S2CID   67753626.
12. Hodnett, John-Paul (2010). "A Machairodont felid (Mammalia; Carnivora; Felidae) from the latest Hemphillian (Late Miocene/Early Pliocene) Bidahochi Formation, northeastern Arizona". Paleobios. 29 (3). doi: 10.5070/P9293021800 .
13. Antón, Mauricio; Salesa, Manuel J.; Siliceo, Gema (2013). "Machairodont Adaptations and Affinities of the Holarctic Late Miocene Homotherin Machairodus (Mammalia, Carnivora, Felidae): The Case of Machairodus Catocopis Cope, 1887". Journal of Vertebrate Paleontology. 33 (5): 1202–1213. Bibcode:2013JVPal..33.1202A. doi:10.1080/02724634.2013.760468. JSTOR   42568635. S2CID   86067845.
14. Antón, Mauricio (2013). Sabertooth. Bloomington, Indiana: University of Indiana Press. p. 123. ISBN   9780253010421.