NEW PRIMITIVE CARNIVORANS (MAMMALIA) FROM THE PALEOCENE OF WESTERN CANADA, AND THEIR BEARING ON RELATIONSHIPS OF THE ORDER

The earliest Carnivora are known from two families, the Miacidae, whic h retain M3/m3 and occur first in latest Paleocene (Clarkforkian) rock s, and the Viverravidae, which have lost M3/m3, but are known first in the middle Paleocene (Torrejonian). This paper describes two new gene ra and species of carnivorans, one (Pristinictis connata) a viverravid and the other (Ravenictis krausei) of uncertain familial affinities, from the early Tiffanian of Alberta and early Puercan of Saskatchewan, respectively; both have a molar structure more primitive than previou sly known for the order. The new carnivorans allow a reassessment of c haracter state polarities in the early evolution of the Carnivora, the reby providing the opportunity for reexamination of the relationships of carnivorans to other eutherian orders. As a consequence of this stu dy, it appears that carnivorans and creodonts share no uniquely derive d character states of the dentition that might indicate they are siste r-groups, and that carnivorans evolved from Cretaceous eutherians less specialized dentally than the Palaeoryctidae.