Haploceratidae
The Haploceratidae is the type family of the Haploceratoidea, a superfamily in the ammonitina; which according to Donovan et al. can be derived from the Taramelliceratinae, a subfamily of the Oppeliidae.
Haploceratids, are typically small, smooth and somewhat featureless ammonites, as described by Arkell et al, without ribbing or ventral keels and moderately undifferentiated sutures; that range from the Late Kimmeridgian to the Hauterivian, crossing from the Jurassic into the Cretaceous.