Hammatoceratoidea, formerly Hammatocerataceae, was a superfamily of middle Jurassic ammonites erected by Schindewolf in 1964 that combined the families Graphoceratidae, Hammatoceratidae, and Sonniniidae.Paleobiology Database Hammatoceratoidea entry The three families were previously included in the Hildoceratoidea, however subsequent classifications have moved the families back into Hildoceratoidea.D.T. Donovan et al., 1981. Classification of Jurassic Ammonitina. The Ammonoidea. Systematics Association special volume 18.
Shells of hammatoceratoids are variably evolute or involute, ribbed at least in the early growth stage; cross section typically compressed (higher than wide); venter commonly with a median keel.
Hammatoceratoids were suggested to be derived from the family Phymatoceratidae of the Hildoceratoidea, beginning with the Hammatoceratidae near the end of the Early Jurassic.
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