Peltephilus ferox (Ameghino 1897; Miocene; 1.5 m long) is yet another armadillo-mimic.Aside from the horned gophers of North America, it is the only known fossorial horned mammal. Among tested taxa it is closest to the tree sloth, Bradypus, rather than the armadillo, Dasypus. No transitional taxa have yet been reported.
The seven teeth (x4) of Peltephilus formed a complete arcade. They were all similar in shape. Apparently (based on the above data), like the similarly short-faced Bradypus, the reduced premaxilla did not extend to the palate. No edentates have premaxillary teeth. In Bradypus the lost premaxilla leaves a space between the anterior maxillae. By contrast, in Peltephilus the maxillae join in medial contact. With that medial migration the canine teeth also migrate medially, taking the place of the absent incisors. The remaining 3 premolars and 3 molars comprise the remainder of the arcade with the molars remaining ventral to the laterally expanded jugals, as in sister taxa.
Postcranially Peltephilus had transverse bands of ossified armor along the back. It had short legs and large claws, ideal for digging or ripping open ant colonies.