Eowellerites is genus of ammonoid cephalopods belonging to the Welleritidae family. Species belonging to this genus lived in middle Pennsylvanian (Moscovian). Its fossils were found in USA and Japan. It had thinly discoidal shells with a quite wide umbilicus (U/D = 0.3 - 0.5). While in juvenile stages (up to 15 mm in diameter) venter is moderately rounded, it becomes slightly rounded to flattened when becoming mature (100 mm in diameter). 12-lobed suture has adventitious lobe on the first lateral saddle and is also characterized by an addition of an umbilical lobe. Sutural formula is (V1 V1) L1 L (U1 U2): I D. It has evolved from Winslowoceras henbesti and gave rise to genus Wellerites.Mapes, Royal H., and Furnish W. M. "The Pennsylvanian Ammonoid Family Welleritidae." Journal of Paleontology 55.2 (1981): 317-30. Web.
