The straight snout and the narrow lower incisors closely packed, suggest that this animal had a different feeding strategy compared to their southern relative, although the teeth of both genera were adapted to deal with abrasive food.

[3] It was a rhino-sized animal, a 2012 study estimated a weight of up to 3.8 tonnes (4.2 short tons), which makes it the largest member of Notoungulata,[4] though this may be an overestimate.

Mixotoxodon is the only notoungulate known to have migrated out of South America during the Great American Interchange.

[12] The cladogram below is based in the study published by Analía Forasiepi and colleagues (2014), showing the position of Mixotoxodon inside Toxodontidae:[13] Pampahippus arenalesi Rhynchippus 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 This list indicates the countries and places where Mixotoxodon fossils have been found.