When discovered in the 19th century and during the following decades,
Phlaocyon was thought to be ancestral to
raccoons because of shared
convergent adaptations toward
hypocarnivorous dentitions, but was the first to discover the canid nature of the middle ear region in
P. leucosteus and
Phlaocyon in now believed to be part of very diverse
clade of hypocarnivorous canids, the
Phlaocyonini, and only distantly related to raccoons.
P. mariae and
P. yatkolai, both known from isolated teeth and fragmentary material, are the largest and most derived species, and both display a tendency away from the
hypocarnivorous dentition of the genus and towards a more
hypercarnivorous dentition. ==Anatomy==