Toxodon platensis
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Notoungulata
Family: Toxodontidae
Owen, 1845
Subfamilies and Genera

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


In 2014, a study identifying a new species of toxodontid resolved the families phylogenetic relations. The below cladogram was found by the study:[1]

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

Ocnerotherium intermedium

Hoffstetterius imperator

Posnanskytherium desaguaderoi

Pisanodon nazari

Pericotoxodon platignathus

Calchaquitherium mixtum

Mixotoxodon larensis

Paratrigodon euguii

Trigodon gaudri

  1. (2014) "New toxodontid (Notoungulata) from the Early Miocene of Mendoza, Argentina". Paläontologische Zeitschrift. DOI:10.1007/s12542-014-0233-5.