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Haploceratoidea

Haploceratoidea, formerly Haplocerataceae, is a superfamily of ammonoid cephalopods belonging to the Ammonitida that unites three families, Strigoceratidae, Oppeliidae, and Haploceratidae, listed below.

Haploceratoidea begins with all three families in the lower Middle Jurassic, Bajocian. Strigoceratidae is limited to the Bajocian but Oppeliidae, and Haploceratidae extend through the remaining Jurassic, well into the Cretaceous; the Oppeliidae into the middle Albian, the Haplocertidae only into the Valanginian.