Elrathina cordillerae (Rominger, 1887) (= Ptychoparella cordillerae)

Name: Elrathina cordillerae (Rominger, 1887) (= Ptychoparella cordillerae)
Locality: Pend Oreille County, Washington
Stratigraphy: Middle Cambrian, Metaline Limestone
Remarks: Left photo courtesy of thenaturalcanvas.com
http://www.thenaturalcanvas.com/Trilobites/pages/2617.html

Right photo: courtesy David Morgan