Hyopsodontidae is an extinct family of primitive mammals, initially assigned to the order Condylarthra, living from the Paleocene to the Eocene in North America and Eurasia. Condylarthra is now thought to be a wastebasket taxon; hyopsodontids have occasionally been speculated to be related to Afrotheria,[1] but the most recent consensus is that they are related to Perissodactyla. Analysis of the inner ear shows shared characteristics with the Equoidea (horses and paleotheres);[2] they may be a basal ungulate group near to perissodactyls.[3]
| Hyopsodontidae | |
|---|---|
| |
| Hyopsodus | |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Clade: | Panperissodactyla |
| Family: | †Hyopsodontidae Trouessart, 1889 |
| Genera | |
|
see text | |
They were generally small omnivores, like many early mammals. The most common genus is Hyopsodus.
Members of the family were small by modern standards, ranging in size from a small rat to a raccoon. The hyopsodontids had many primitive mammal characteristics, including five-toed feet with claws and a complete dentition: a full set of incisors, canines, premolars, and molars. During the Paleocene in Europe, they reached a high diversity level, starting with Louisina and Monshyus in Hainin, Belgium, and following in the Cernaysian beds with Tricuspiodon, Paratricuspiodon, and Paschatherium.[4] High levels of diversity are also seen in Western North America in the Eocene within the genus Hyopsodus, with up to 18 named species, some of which are specific to particular locations over short spans of geologic time. This pattern suggests that at least some hyosodontids became quite specialized for specific ways of life. The group was not especially long-lived, but highly successful for its time, with fossil material in some areas suggesting large numbers of individuals.[5]
References
edit- ^ Tabuce, Rodolphe; Marivaux, Laurent; Adaci, Mohammed; Bensalah, Mustapha; Hartenberger, Jean-Louis; Mahboubi, Mohammed; Mebrouk, Fateh; Tafforeau, Paul; Jaeger, Jean-Jacques (2007). "Early Tertiary mammals from North Africa reinforce the molecular Afrotheria clade". Proceedings of the Royal Society B: Biological Sciences. 274 (1614): 1159–1166. doi:10.1098/rspb.2006.0229. PMC 2189562. PMID 17329227.
- ^ Ravel, Anthony; Orliac, Maeva J. (2015). "The inner ear morphology of the 'condylarthran'Hyopsodus lepidus". Historical Biology. 27 (8): 957–969. doi:10.1080/08912963.2014.915823. S2CID 84391276.
- ^ Orliac, Maeva J.; Argot, Christine; Gilissen, Emmanuel (2012-02-10). "Digital Cranial Endocast of Hyopsodus (Mammalia, "Condylarthra"): A Case of Paleogene Terrestrial Echolocation?". PLOS ONE. 7 (2): e30000. Bibcode:2012PLoSO...730000O. doi:10.1371/journal.pone.0030000. ISSN 1932-6203. PMC 3277592. PMID 22347998.
- ^ Agusti, Jordi; Anton, Mauricio (2002). Mammoths, Sabertooths, and Hominids: 65 Million Years of Mammalian Evolution in Europe. Columbia University Press. ISBN 0-231-11640-3..
- ^ Flynn, John J. (1991). "Hyopsodus (Mammalia) from the Tepee Trail Formation (Eocene), Northwestern Wyoming" (PDF). American Museum Novitates – via Digital Library of the American Museum of Natural History, New York.
- ^ Kihm, A.J.; Hartman, J.H. (December 2004). "A reevaluation of the biochronology of the Brisbane and Judson local faunas (late Paleocene) of North Dakota". Bulletin of Carnegie Museum of Natural History. 2004 (36): 97–107. doi:10.2992/0145-9058(2004)36[97:AROTBO]2.0.CO;2.
- ^ Burger, B.J. (July 2007). "A new Late Paleocene vertebrate fauna from the Ohio Creek Formation of Western Colorado". Mountain Geologist. 44 (3): 141–150. Retrieved 14 August 2020.
- ^ Robinson, P.; Williams, B.A. (May 1997). "Species diversity, tooth size, and shape of Haplomylus (Condylarthra, Hyopsodontidae) from the Powder River basin, northeastern Wyoming". Rocky Mountain Geology. 31 (2): 59–78. Retrieved 14 August 2020.
- ^ Williamson, T.E.; Weil, A. (June 2011). "A New Puercan (Early Paleocene) Hyopsodontid "Condylarth" from New Mexico". Acta Palaeontologica Polonica. 56 (2): 247–255. doi:10.4202/app.2009.0147. S2CID 54639945.
- ^ Rose, K.D.; Storch, G.; Krohmann, K. (November 2013). "Small-mammal postcrania from the middle Paleocene of Walbeck, Germany". Paläontologische Zeitschrift. 89: 95–124. doi:10.1007/s12542-013-0211-3. S2CID 84072639.
- ^ Zack, S.P.; Penkrot, T.A.; et al. (2005). "A new apheliscine "condylarth" mammal from the late Paleocene of Montana and Alberta and the phylogeny of "hyopsodontids"" (PDF). Acta Palaeontologica Polonica. 50 (4): 809–830. Retrieved 14 August 2020.
- ^ Thewisson, J.G.M. (1991). "Limb Osteology and function of the primitive Paleocene ungulate Pleuraspidotherium with notes on Tricuspiodon and Dissacus (Mammalia)". Geobios. 24 (4): 483–495. doi:10.1016/S0016-6995(06)80249-4.