Janassa clarki

We have found only one single tooth of Janassa in the Bear Gulch Limestone. This tooth closely resembles those of Janassa bituminosa from the Permian of Germany, as well as Janassa sp. from the Pennsylvanian of Illinois. It differs in having a more rounded profile of the extended lingual "heel", which is wider than the crown.  The scale is in mm.

Reference:

• Lund, R. 1989. "New petalodonts (Chondrichthyes) from the Upper Mississippian Bear Gulch Limestone (Namurian E2b) of Montana." J. Vert. Paleo. 9:350-368.

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