Effective: September 19, 1985
Latest Legislation: House Bill 145 - 116th General Assembly
Isotelus, a genus of extinct marine arthropod of the class Trilobita, that lived in the seas that covered Ohio during the Ordovician period, about four hundred forty million years ago, and represented by the largest known complete trilobite, collected at Huffman dam in Montgomery county, is hereby adopted as the official invertebrate fossil of the state.