Toxodontidae

Toxodontidae; Temporal range: Late Oligocene (Deseadan)-Holocene; ~23–0.011 Ma PreꞒ Ꞓ O S D C P T J K Pg N
	Mixotoxodon larensis
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	†Notoungulata
Family:	†Toxodontidae; Owen 1845
Subfamilies and genera
	†Haplodontheriinae †Abothrodon; †Haplodontherium; †Mesotoxodon; †Mixotoxodon; †Ocnerotherium; †Pachynodon; †Paratrigodon; †Prototrigodon; †Toxodontherium; †Trigodon; †Trigodonops; †Nesodontinae †Adinotherium; †Nesodon; †Palyeidodon; †Posnanskytherium; †Proadinotherium; †Toxodontinae †Andinotoxodon; †Ceratoxodon; †Chapalmalodon; †Dinotoxodon; †Eutomodus; †Gyrinodon; †Hemixotodon; †Hyperotoxodon; †Mesenodon; †Minitoxodon; †Neoadinotherium; †Neotoxodon; †Nesodonopsis; †Nonotherium; †Pericotoxodon; †Piauhytherium; †Pisanodon; †Plesiotoxodon; †Stenotephanos; †Stereotoxodon; †Toxodon; †Xotodon;

Toxodontidae is an extinct family of notoungulate mammals, known from the Oligocene to the Holocene (11,000 BP) of South America,[1] with one genus, Mixotoxodon, also known from the Pleistocene of Central America and southwestern North America (Texas).[2] They somewhat resembled rhinoceroses, and had teeth with high crowns and open roots, suggesting that they often fed on tough pampas grass.[3] However, isotopic analyses have led to the conclusion that the most recent forms were grazing and browsing generalists.[4]

Xotodon sp. skull at the Museum für Naturkunde, Berlin

Taxonomy

The endemic notoungulate and litoptern ungulates of South America have been shown by studies of collagen and mitochondrial DNA sequences to be a sister group to the perissodactyls.[5][6][7]

In 2014, a study identifying a new species of toxodontid resolved the families phylogenetic relations. The below cladogram was found by the study:[8]

Pampahippus arenalesi

Rhynchippus spp.

	Scarritia canquelensis

	Leonitinia gaudri

Toxodontidae

Proadinotherium leptognathum

Adinotherium spp.

	Nesodon taweretus

	Nesodon imbricatus

Palyeidodon obtusum

Hyperoxotodon speciosus

	Nonotherium henningi

	Xotodon spp.

Andinotoxodon bolivariensis

	Dinotoxodon paranensis

	Toxodon platensis

Gyrinodon quassus

	Ocnerotherium intermedium

	Hoffstetterius imperator

Posnanskytherium desaguaderoi

Pisanodon nazari

Pericotoxodon platignathus

	Calchaquitherium mixtum

	Mixotoxodon larensis

	Paratrigodon euguii

	Trigodon gaudri

References

Turvey, Samuel T. (2009-05-28). Holocene Extinctions. OUP Oxford. ISBN 9780191579981.
E. Lundelius, et al. 2013. The first occurrence of a toxodont (Mammalia, Notoungulata) in the United States. Journal of Vertebrate Paleontology, Vol 33, No 1, pp. 229–232 DOI:10.1080/02724634.2012.711405
Palmer, D., ed. (1999). The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals. London: Marshall Editions. p. 253. ISBN 978-1-84028-152-1.
MacFadden, Bruce J. (September 2005). "Diet and habitat of toxodont megaherbivores (Mammalia, Notoungulata) from the late Quaternary of South and Central America". Quaternary Research. 64 (2): 113–124. Bibcode:2005QuRes..64..113M. doi:10.1016/j.yqres.2005.05.003.
Welker, F.; Collins, M. J.; Thomas, J. A.; Wadsley, M.; Brace, S.; Cappellini, E.; Turvey, S. T.; Reguero, M.; Gelfo, J. N.; Kramarz, A.; Burger, J.; Thomas-Oates, J.; Ashford, D. A.; Ashton, P. D.; Rowsell, K.; Porter, D. M.; Kessler, B.; Fischer, R.; Baessmann, C.; Kaspar, S.; Olsen, J. V.; Kiley, P.; Elliott, J. A.; Kelstrup, C. D.; Mullin, V.; Hofreiter, M.; Willerslev, E.; Hublin, J.-J.; Orlando, L.; Barnes, I.; MacPhee, R. D. E. (2015-03-18). "Ancient proteins resolve the evolutionary history of Darwin's South American ungulates". Nature. 522 (7554): 81–84. Bibcode:2015Natur.522...81W. doi:10.1038/nature14249. ISSN 0028-0836. PMID 25799987. S2CID 4467386.
Buckley, M. (2015-04-01). "Ancient collagen reveals evolutionary history of the endemic South American 'ungulates'". Proceedings of the Royal Society B: Biological Sciences. 282 (1806): 20142671. doi:10.1098/rspb.2014.2671. PMC 4426609. PMID 25833851.
Westbury, M.; Baleka, S.; Barlow, A.; Hartmann, S.; Paijmans, J. L. A.; Kramarz, A.; Forasiepi, A. M.; Bond, M.; Gelfo, J. N.; Reguero, M. A.; López-Mendoza, P.; Taglioretti, M.; Scaglia, F.; Rinderknecht, A.; Jones, W.; Mena, F.; Billet, G.; de Muizon, C.; Aguilar, J. L.; MacPhee, R. D. E.; Hofreiter, M. (2017-06-27). "A mitogenomic timetree for Darwin's enigmatic South American mammal Macrauchenia patachonica". Nature Communications. 8: 15951. Bibcode:2017NatCo...815951W. doi:10.1038/ncomms15951. PMC 5490259. PMID 28654082.
Forasiepi, A. A. M.; Cerdeño, E.; Bond, M.; Schmidt, G. I.; Naipauer, M.; Straehl, F. R.; Martinelli, A. N. G.; Garrido, A. C.; Schmitz, M. D.; Crowley, J. L. (2014). "New toxodontid (Notoungulata) from the Early Miocene of Mendoza, Argentina". Paläontologische Zeitschrift. 89 (3): 611–634. doi:10.1007/s12542-014-0233-5. S2CID 129293436.

Toxodontidae Temporal range: Late Oligocene (Deseadan)-Holocene ~23–0.011 Ma PreꞒ Ꞓ O S D C P T J K Pg N

Mixotoxodon larensis
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	†Notoungulata
Family:	†Toxodontidae Owen 1845
Subfamilies and genera
†Haplodontheriinae †Abothrodon †Haplodontherium †Mesotoxodon †Mixotoxodon †Ocnerotherium †Pachynodon †Paratrigodon †Prototrigodon †Toxodontherium †Trigodon †Trigodonops †Nesodontinae †Adinotherium †Nesodon †Palyeidodon †Posnanskytherium †Proadinotherium †Toxodontinae †Andinotoxodon †Ceratoxodon †Chapalmalodon †Dinotoxodon †Eutomodus †Gyrinodon †Hemixotodon †Hyperotoxodon †Mesenodon †Minitoxodon †Neoadinotherium †Neotoxodon †Nesodonopsis †Nonotherium †Pericotoxodon †Piauhytherium †Pisanodon †Plesiotoxodon †Stenotephanos †Stereotoxodon †Toxodon †Xotodon

Toxodontidae

Taxonomy

References

Further reading