Amphicynodontidae

Amphicynodontidae is a probable clade of extinct arctoids. While some researchers consider this group to be an extinct subfamily of bears,^[1] a variety of morphological evidence links amphicynodontines with pinnipeds, as the group were semi-aquatic otter-like mammals.^[2][3][4] In addition to the support of the pinniped–amphicynodontine clade, other morphological and some molecular analyses support bears being the closest living relatives to pinnipeds.^{[5][6][7][3][8][4]} According to McKenna and Bell (1997) Amphicynodontinae are classified as stem-pinnipeds in the superfamily Phocoidea.^[9] Fossils of these mammals have been found in Europe, North America and Asia.^[4] Amphicynodontines should not be confused with Amphicyonids (bear-dogs), a separate family of Carnivora which is a sister clade to arctoids within the caniforms, but which may be listed as a clade of extinct arctoids in older publications.

Amphicynodontidae Temporal range: Late Eocene to Early Miocene 38–18 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Artist's restoration of Kolponomos newportensis.
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Carnivora
Clade:	Pan-Pinnipedia
Family:	†Amphicynodontidae Simpson, 1945
Genera
†Allocyon †Amphicticeps †Amphicynodon †Drassonax †Kolponomos †Pachycynodon †Wangictis

Systematics

• Family †Amphicynodontidae Simpson, 1945^[10]
  • †Allocyon Merriam, 1930
    • †Allocyon loganensis Merriam, 1930
  • †Amphicynodon Filhol, 1881
    • †Amphicynodon brachyrostris (Filhol, 1876)
    • †Amphicynodon cephalogalinus Teilhard, 1915
    • †Amphicynodon chardini Cirot and De Bonis, 1992
    • †Amphicynodon crassirostris (Filhol, 1876)
    • †Amphicynodon gracilis (Filhol, 1874)
    • †Amphicynodon leptorhynchus (Filhol, 1874)
    • †Amphicynodon mongoliensis Janovskaja, 1970
    • †Amphicynodon teilhardi Matthew and Granger, 1924
    • †Amphicynodon typicus Schlosser, 1888
    • †Amphicynodon velaunus (Aymard, 1846)
  • †Amphicticeps Matthew and Granger, 1924
    • †Amphicticeps dorog Wang et al., 2005
    • †Amphicticeps makhchinus Wang et al., 2005
    • †Amphicticeps shackelfordi Matthew and Granger, 1924
  • †Drassonax Galbreath, 1953
    • †Drassonax harpagops Galbreath, 1953
  • †Kolponomos Stirton, 1960
    • †Kolponomos clallamensis Stirton, 1960
    • †Kolponomos newportensis Tedford et al., 1994
  • †Pachycynodon Schlosser, 1888
    • †Pachycynodon boriei (Filhol, 1876)
    • †Pachycynodon crassirostris Schlosser, 1888
    • †Pachycynodon filholi Schlosser, 1888
    • †Pachycynodon tenuis Teilhard de Chardin, 1915
  • †Wangictis de Bonis et al., 2019
    • †Wangictis tedfordi (Wang & Qiu, 2003)

References

1. McLellan, B.; Reiner, D.C. (1992). "A review of bear evolution" (PDF). International Association for Bear Research and Management. 9 (1): 85–96. doi:10.2307/3872687. JSTOR 3872687. S2CID 91124592. Archived from the original (PDF) on 19 February 2020.
2. Tedford, R. H.; Barnes, L. G.; Ray, C. E. (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. Archived from the original (PDF) on 22 September 2012. Retrieved 24 July 2010.
3. Rybczynski, N.; Dawson, M.R.; Tedford, R.H. (2009). "A semi-aquatic Arctic mammalian carnivore from the Miocene epoch and origin of Pinnipedia". Nature. 458 (7241): 1021–24. Bibcode:2009Natur.458.1021R. doi:10.1038/nature07985. PMID 19396145. S2CID 4371413.
4. Berta, A.; Morgan, C.; Boessenecker, R.W. (2018). "The Origin and Evolutionary Biology of Pinnipeds: Seals, Sea Lions, and Walruses". Annual Review of Earth and Planetary Sciences. 46: 203–228. Bibcode:2018AREPS..46..203B. doi:10.1146/annurev-earth-082517-010009.
5. Hunt, R. M. Jr.; Barnes, L. G. (1994). "Basicranial evidence for ursid affinity of the oldest pinnipeds" (PDF). Proceedings of the San Diego Society of Natural History. 29: 57–67.
6. Lento, G. M.; Hickson, R. E.; Chambers, G. K.; Penny, D. (1995). "Use of spectral analysis to test hypotheses on the origin of pinnipeds". Molecular Biology and Evolution. 12 (1): 28–52. doi:10.1093/oxfordjournals.molbev.a040189. PMID 7877495.
7. Wang, X.; McKenna, M. C.; Dashzeveg, D. (2005). "Amphicticeps and Amphicynodon (Arctoidea, Carnivora) from Hsanda Gol Formation, central Mongolia and phylogeny of basal arctoids with comments on zoogeography". American Museum Novitates (3483): 216. doi:10.1206/0003-0082(2005)483[0001:AAAACF]2.0.CO;2. hdl:2246/5674.
8. Higdon, J. W.; Bininda-Emonds, O. R.; Beck, R. M.; Ferguson, S. H. (2007). "Phylogeny and divergence of the pinnipeds (Carnivora: Mammalia) assessed using a multigene dataset". BMC Evolutionary Biology. 7: 216. doi:10.1186/1471-2148-7-216. PMC 2245807. PMID 17996107.
9. McKenna, M.C.; Bell, S. (1997). Classification of Mammals Above the Species Level. Columbia University Press, New York.
10. Amphicynodontinae in the Paleobiology Database