This is Trilobite Tuesday post #8. Please note: most of the information used here came from the State Fossil page on Fossilera. It has information on all the state fossils, including state dinosaurs and state "stones". They have nice pictures and a brief description with links for each one.
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All but seven states have state fossils. And, there are three types of trilobite that have been honored as state fossils. Those types are listed below.
Ohio State Fossil
Isotelus
Age: Ordovician
Year Designated: 1985
Isotelus is a genus to large Asaphid trilobite that lived during the Ordovician Period. It’s fossils are common within several formations that outcrop in Southwestern Ohio. The largest Isotelus trilobite to be found in Ohio is about 16 inches long though the largest known trilobite Isotelus rex found in Manitoba, Canada is from the same genus.
The most famous specimen of Isotelus from Ohio was discovered in 1919 while digging an outlet tunnel during the construction of the Huffman Dam near Dayton. This giant trilobite specimen measures 14 ½ inches long. A couple elementary school classes in Dayton proposed naming this specimen of the official state fossil. While declining to designate only that specific specimen, the legislature instead passed a bill naming the genus Isotelus in 1985.
Pennsylvania State Fossil
Eldredgeops rana
Age: Devonian
Year Designated: 1988
Phacops may be the most widely recognizable type of trilobite fossil in the world. Phacops rana is a species of the genus that can found in Pennsylvania's Devonian aged rocks. Trilobites are an extinct marine arthropod that occurred abundantly during the Paleozoic era.
Phacops rana was named the official state fossil of Pennsylvania in 1988 after being proposed to lawmakers by a elementary school science class. It has recently been declared synonymous with Eldredgeops rana.
Wisconsin State Fossil
Calymene celebra
Age: Silurian
Year Designated: 1985
In 1985 the trilobite Calymene celebra was adopted as the official Wisconsin state fossil. Trilobites are extinct marine arthropods which dominated the seas during the Paleozoic period. Calymene celebra lived during the Silurian period, at a time when warm, shallow seas covered the state. Its fossils are common in the vast Niagara dolomite outcroppings which are exposed in the state.
This species of trilobite is fairly common in Illinois. Of course, you have to find a place to get under the glacial till on top of our limestone bedrock.
