Kingdom Animalia Class †Tentaculita Family †Tentaculitidae | Phylum Mollusca (?) Order †Tentaculitida Genus †Tentaculites | |
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Tentaculites oswegoensis is a small animal of unknown origin that is often classified with molluscs or even as marine worms with a hard body. The genus Tentaculites was named in 1820 by von Schlotheim. This particular species was named by at least 1877 and is known from the Upper Ordovician rocks of the Maquoketa Group. It ranged from Oswego, IL (Kendall County) to possibly Kankakee River State Park (KRSP) in Will County, Illinois. At KRSP it appears in the basal Silurian of the Kankakee Formation but has not been found in the underlying Ordovician rocks.
This particular species is approximately 0.75 to 1.25 inches in length. In Oswego, Illinois it is found mostly in clusters at Waubonsie Creek in the Basal Brainard Formation, just west of the railroad tracks. This entire class of animal became extinct at the end of the Devonian and leaves no known descendants or related species.