Gyroptychius agassizi (Traill)

Reconstruction. A: lateral and B: dorsal view (after Jarvik, 1948) ©.
This osteolepid fish was the largest of its kind in the Sandwick Fish Bed sediments. It’s almost symmetrical tail and fin position make it easy to distinguish from the other osteolepids.
Normally in the Sandwick Fish Bed, this species is found one for every ten of Osteolepis specimens. It probably preyed on everything small enough to be swallowed whole. It is found in the Sandwick Fish Bed only.