Trilobites are marine invertebrates that lived more than 500 million years ago. Roaming the floor of the Cambrian-era sea for food, these hard-shelled creatures were prolific and represent a diverse and vibrant life form.
The name refers to the three-part shape of the trilobite:
and the three hard shells that comprise the exoskeleton:
the middle axial lobe
the left pleural lobe
the right pleural lobe
Several different trilobite species are found in Utah in a broken band of Cambrian limestones, siltstones, and shales that trends across the western part of the state. These specimens are Elrathia kingi common to the trilobite beds west of Delta, Utah.