Sansanosmilus

Sansanosmilus Temporal range: Middle-Late Miocene (Burdigalian to Tortonian), 16–11.4  Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Skull of S. palmidens
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Carnivora
Family:	† Nimravidae
Tribe:	† Barbourofelini
Genus:	† Sansanosmilus Kretzoi, 1929
Type species
Sansanosmilus palmidens Kretzoi, 1929
Other Species
Sansanosmilus rhomboidalis Sansanosmilus serratus

Sansanosmilus is an extinct genus of carnivorous mammal of the subfamily, Barbourofelinae and was found in Eurasia and lived during the Miocene from 16 to 11.4 mya, existing for 4.6 million years. ^{[1] [2] Including supplementary materials}

Taxonomy

Sansanosmilus is a member of the group of feiliforms known as barbourofelids, once considered to being a separate family of feliforms ^{[3] [4] [5] [6]} , now widely considered to be a subfamily of nimravids. ^{[7] [8] [9] [1] [10] [11]}

Although Albanosmilus was seen as a junior synonym of Sansanosmilus from the 1970s onwards, Robles et al. (2013) demonstrated that the type species of Albanosmilus, A. jourdani (which they considered to be a senior synonym of S. vallesiensis), is more closely related to Barbourofelis than to the type species of Sansanosmilus and thus generically distinct. ^[5] Wang et al. (2020) agreed with Robles et al. (2013) in recovering Albanosmilus as closer to Barbourofelis than to Sansanosmilus. ^[11]

A further two species of Sansanosmilus (S. rhomboidalis and S. serratus) were described by G.E. Pilgrim in 1932 based on fragmentary fossils from the Siwaliks. ^[12] Sansanosmilus rhomboidalis was described further, with new material assigned, in 2022. ^[13]

Description

S. palmidens and Necromanis

Sansanosmilus had short legs, was very muscular and had a long tail. Sansanosmilus palmidens is believed to have been leopard-sized. ^[14] S. palmidens is known from its well developed machairodont specialization in its skull, but with moderate saber teeth. Compared to Barbourofelis, it had smaller canines, less blade-like carnassials, and less derived mastoid region. In 1961, paleontologist L. Ginsburg concluded that Sansanosmilus was possessed of a plantigrade walking stance, after studying its foot bones and comparing it with those of the true felid Pseudaelurus from the same site. This is different from later barbourofelins, which are believed to have had semi-plantigrade or semi-digitigrade stances. ^[15]

Paleobiology

According to a 2012 study, S. palmidens had a jaw gape of 73°. The authors found based on the jaw anatomy of S. palmidens and other sabertooth predators, instead of being more suited of hunting megahberivores, they were better suited for delivering deeper bites on smaller to medium sized prey. ^{[16] Including supplementary materials} A 2020 study found that S. palmidens had an even lower jaw gape of 53°. ^{[17] Including supplementary materials}

Paleoecology

The type species, Sansanosmilus palmidens, is known from fossils from the Orleanian and Astaracian stages in France from 16 to 13 ma. ^{[2] Including supplementary materials}

References

1. Jasinski, Steven E.; Abbas, Ghyour; Mahmood, Khalid; et al. (November 2022). "New Carnivoran (Mammalia: Carnivora) specimens from the Siwaliks of Pakistan and India and their faunal and evolutionary implications". Historical Biology. 35 (11): 1–35. doi:10.1080/08912963.2022.2138376.
2. Barrett, Paul Zachary (26 October 2021). "The largest hoplophonine and a complex new hypothesis of nimravid evolution". Scientific Reports. 11 (1): 21078. Bibcode:2021NatSR..1121078B. doi: 10.1038/s41598-021-00521-1 . PMC   8548586 . PMID   34702935. S2CID   240000358.
3. Morlo, Michael; Peigné, Stéphane; Nagel, Doris (2004). "A new species of Prosansanosmilus: implications for the systematic relationships of the family Barbourofelidae new rank (Carnivora, Mammalia)". Zoological Journal of the Linnean Society. 140 (1): 43–61. doi: 10.1111/j.1096-3642.2004.00087.x .
4. Werdelin, L.; Yamaguchi, N.; Johnson, W. E. & O'Brien, S. J. (2010). "Phylogeny and evolution of cats (Felidae)". In Macdonald, D. W. & Loveridge, A. J. (eds.). Biology and Conservation of Wild Felids. Oxford, UK: Oxford University Press. pp. 59–82. ISBN   978-0-19-923445-5.
5. Josep M. Robles; David M. Alba; Josep Fortuny; Soledad De Esteban-Trivigno; Cheyenn Rotgers; Jordi Balaguer; Raül Carmona; Jordi Galindo; Sergio Almécija; Juan V. Bertó & Salvador Moyà-Solà (2013). "New craniodental remains of the barbourofelid Albanosmilus jourdani (Filhol, 1883) from the Miocene of the Vallès-Penedès Basin (NE Iberian Peninsula) and the phylogeny of the Barbourofelini". Journal of Systematic Palaeontology. 11 (8): 993–1022. doi:10.1080/14772019.2012.724090. S2CID   85157737.
6. Morales, Jorg; Pickford, Martin (2018). "A new barbourofelid mandible (Carnivora, Mammalia) from the Early Miocene ofGrillental-6, Sperrgebiet, Namibia". Communications of the Geological Survey of Namibia. 18: 113–123.
7. Barrett, Paul Z.; Hopkins, Samantha; Price, Samantha A. (2021). "How many sabertooths? Reevaluating the number of carnivoran sabertooth lineages with total-evidence Bayesian techniques and a novel origin of the Miocene Nimravidae". Journal of Vertebrate Paleontology. 41 (1). Bibcode:2021JVPal..41E3523B. doi:10.1080/02724634.2021.1923523. S2CID   236221655.
8. Barret, Paul Z.; Hopkins, Samatha S. B. (2024). "Mosaic evolution underlies feliform morphological disparity". Proc. R. Soc. B. 291 (2028).
9. Barret, Paul (October 26, 2021). "The largest hoplophonine and a complex new hypothesis of nimravid evolution". nature. 11 (1). doi: 10.1038/s41598-021-00521-1 . PMC   8548586 .
10. Werdelin, Lars (November 2021). "African Barbourofelinae (Mammalia, Nimravidae): a critical review". Historical Biology. 34 (2): 1–9. doi:10.1080/08912963.2021.1998034.
11. Wang, Xiaoming; White, Stuart C.; Guan, Jian (2020). "A new genus and species of sabretooth, Oriensmilus liupanensis (Barbourofelinae, Nimravidae, Carnivora), from the middle Miocene of China suggests barbourofelines are nimravids, not felids" . Journal of Systematic Palaeontology. 18 (9): 783–803. doi:10.1080/14772019.2019.1691066. S2CID   211545222.
12. Pilgrim, G.E. (1932). "The fossil Carnivora of India". Mem. Geol. Sur. Ind. Palaeont. Ind. New Series. 18: 1–232.
13. Mahmood, Khalid (2023). "Barbourofelines from the Middle-Late Miocene of the Siwaliks, Pakistan". Pakistan Journal of Zoology. doi: 10.17582/journal.pjz/20221013201049 . S2CID   257513528.
14. Antón, Mauricio (2013). Sabertooth. Bloomington, Indiana: University of Indiana Press. p. 99-100. ISBN   978-0-253-01042-1.
15. Anton, Mauricio (2013). Sabertooth. ISBN   978-0-253-01042-1.
16. Andersson, K.; Norman, D.; Werdelin, L. (2011). "Sabretoothed carnivores and the killing of large prey". PLOS ONE. 6 (10) e24971. Bibcode:2011PLoSO...624971A. doi: 10.1371/journal.pone.0024971 . PMC   3198467 . PMID   22039403.
17. Lautenschlager, Stephan; Figueirido, Borja; Cashmore, Daniel D.; Bendel, Eva-Maria; Stubbs, Thomas L. (2020). "Morphological convergence obscures functional diversity in sabre-toothed carnivores". Proceedings of the Royal Society B . 287 (1935): 1–10. doi: 10.1098/rspb.2020.1818 . ISSN   1471-2954. PMC   7542828 . PMID   32993469.