| Haplocerataceae Temporal range: Bajocian–Albian |
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|---|---|
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Cephalopoda |
| Subclass: | †Ammonoidea |
| Order: | †Ammonitida |
| Suborder: | †Ammonitina |
| Superfamily: | †Haplocerataceae Zittel, 1884 |
| Families | |
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see text |
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Haplocerataceae is a superfamily of ammonoid cephalopods belonging to the Ammonitida that unites three families, the Strigoceratidae, Oppeliidae, and Haploceratidae, listed below.
The Haplocerataceae begins with all three families in the lower Middle Jurassic, Bajocian. The Strigoceratidae is limited to the Bajocian but the Oppeliidae, and Haploceratidae extend through the remaining Jurassic, well into the Cretaceous; the Oppeliidae into the middle Albian, the Haplocertidae only into the Valanginian.
Haplocerataceae are typically compressed, discoidal Ammontida that may be keeled or unkeeled, tending to be oxyconic, with usually falcoid or falcate ribbing. The aptychi are paired and differ between families and have been found in situ in e.g. Oppelia subrudiata and in Pseudolissoceras.
The Origin of the Haplocerataceae is undetermined but it is likely all three component families have their beginnings in the Hammatoceratidae in the middle Bajocian. None of the Haplocerataceae is though to have given rise to any subsequent group.
Superfamily Haplocerataceae Zittel, 1884