Oxycerites is an extinct ammonoid cephalopod belonging to the haploceratacean family, Oppeliidae, that lived during the Middle Jurassic. Shells of Oxycerites are involute, compressed and generally smooth with a sharply rounded venter on the outer rim, deeply impressed dorsum on the inner rim, and a small umbilicus. The living chamber takes up slightly more than half a whorl. Oxycerites grew to a diameter of at least 17.5 cm, about 7 inches. Oppelia and Oecotraustes are similar and closely related forms. Oppelia is smoother, Oecotraustes more strongly ribbed