I was going through my trilobite pygidiums and cephalons from the Winterset of the Pennsylvanian Kansas City group and I found this cephalon that seems different from the others I have. In particular, the genal spine seems curved. In the photos you can see both the internal mold and, in the other half of the split, the inside of the shell. I assume the pygidium beside it is belongs to the same creature, but I could be wrong. Any help with the ID will be appreciated.
Russ