Dire Wolf vs Bear Dog Carnassials

One distinction between this dire wolf tooth and the bear dog tooth that is evident in the image is a difference in the talonid, the platform that lies behind the central cusp of the lower carnassial teeth.

The dire wolf (and other canids) has a talonid that may appear in a side-view to be either flat or low-rimmed. It has, in fact, a depressed area in the center, a "basin" with labial and lingual sides of the basin rising to about the same level -- a basined talonid.

In bear dogs, this rear third of the m1 appears in a lateral view to have an inflated cusp on the labial side. The inflated cusp makes the talonid appear bladelike, not flat or equal-sided as in canids. This cusp is called a "hypoconid". The hypoconid cusp crowds the small cusp on the lingual side of the talonid. The cusp provides another shearing edge, so you can refer to it as "a secant (cutting) hypoconid."

If this is too much detail, just remember, "canid - basined talonid"; "amphicyonid - secant talonid."