This has the usual features of a trilobite in the family Trincleidae -- it is blind (no eyes), has a short body with long genal spines, and several rows of "dots" along the rim of the head. However this differs from Cryptolithus and Onnia in that those two species each have a central occipital spine, while this species has two spines coming from the back of the head, on the far left and the far right. These are distinct from, and to a degree lie on top of, the genal spines.

In Cyrptolithus and Onnia the "dots" are pits. And in cranidia of limestone preserved Tretaspis specimens, they are also pits. See "The Trilobite Tretaspis From the Upper Ordovician of the Oslo Region, Norway" Yet in this specimen the "dots" are bumps (convex, not concave). See the last photograph. In that picture the only light came from the left side, so the fact that the dots are illuminated on the left and shadowed on the right shows that they are bumps, not pits. Despite the good preservation of the spines this appears to be largely if not entirely a "naked trilobite", i.e., an internal mold rather than the shell itself.