This species of trilobite has been known by Paleontologists and collectors alike for many years. There has never been a complete specimen found. However many segments of this trilobite have been found and based on those fossils a life-size reconstruction was made by George Rennie under the guidance and research by Dr. Copeland McClintock of Yale University Division of Invertebrate Paleontology. At this time the original model is on display at the Peabody Museum at Yale. To date this trilobite is considered to be the largest in the world. Terataspis is found in both the lower Onondaga Limestone (middle Devonian of western New York, particularly the former Fogelsanger Quarry in Williamsville, Erie County, and the upper Schoharie Formation of eastern New York. The large size and spiny nature of this trilobite make it one of the more spectacular forms.
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That's nightmare fuel? These existed.