Its body was probably massive, and the animal reached a considerable size, about 1.8 meters in length.

Its legs were strong and sturdy, with a general appearance probably resembling that of a modern bear.

Arminiheringia was a typical member of the family Proborhyaenidae, a clade of South American bear-like metatherians.

Those animals belonged to the order Sparassodonta, a clade related to marsupials whose members, during the course of their evolution, occupied niches ordinarily occupied on other continents by carnivores.

Its strong, sturdy body and its skull armed with large teeth are typical indicators of a carnivorous diet ; the strange lower canines, elongated forwards, indicates that Arminiheringia was a specialised predator, although its hunting techniques are still a mystery.