Rare Ceraurus globulobatus Trilobite from Canada

This plate displays a rarely seen example of the Cheirurud trilobite Ceraurus globulobatus found in the Middle Ordovician Trenton Group deposits of Simcoe County, Ontario, Canada. This one is different from most trilobites of the region in large measure due to the sweeping genal, pleural, and pygidial spines. The spines presumably in addition to a deterrent to predators probably served to keep the trilobite near the surface of the substrate, much as snowshoes do. Notice that there is a portion of a second cephalon positioned just to the right of the specimen. Due to the differences in the shape of the genal spine, that is an entirely different example of these wonderfully diverse trilobites from the region.