Pakasuchus: a cat-sized reptile with mammalian tooth patterns.
The fossil of this cat-sized reptile was found by a National Science Foundation grantee in Tanzania.
The unusual feature were the molar-like teeth that showed mammalian-like chewing habits (instead of simply tearing food to shreds like a reptile would). I was lucky to work with the researcher while he was in the field. As I was visualizing the life-like habit of this creature, pieces of the anatomy were still in the rock matrix! But the researcher made some educated guesses as to what those should look like.