Toxodontid

Toxodontidae Temporal range: Late Oligocene–late Pleistocene PreЄ Є O S D C P T J K Pg N
Mixotoxodon larensis
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	†Notoungulata
Suborder:	†Toxodonta
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

Haplodontheriinae

†Nesodontinae

Toxodontinae

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

The notoungulate and litoptern native ungulates of South America have been shown by studies of collagen and mitochondrial DNA sequences to be a sister group to the perissodactyls.

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

Pampahippus arenalesi

Rhynchippus spp.

Scarritia canquelensis

Leonitinia gaudri

Proadinotherium leptognathum

Adinotherium spp.

Nesodon taweretus

Nesodon imbricatus

Palyeidodon obtusum

Hyperoxotodon speciosus

Nonotherium henningi

Xotodon spp.

Andinotoxodon bolivariensis

Dinotoxodon paranensis

Toxodon platensis

Gyrinodon quassus

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Wikipedia