Hammatoceratoidea
| Hammatoceratoidea Temporal range:
| |
|---|---|
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Cephalopoda |
| Subclass: | †Ammonoidea |
| Order: | †Ammonitida |
| Suborder: | †Ammonitina |
| Superfamily: | †Hammatoceratoidea Schindewolf 1964 |
| Families | |
Hammatoceratoidea, formerly Hammatocerataceae is a superfamily of middle Jurassic ammonites (order Ammonitida), erected by Schindewolf (1964) that combines the families Graphoceratidae, Hammatoceratidae, and Soninniidae.[1] The three families were previously included in the Hildocerataceae,[2] and subsequent classifications.[3] In more recent classifications Hammotocerataceae are referred to as Hammatoceratoidia.
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.
Hammatoceratoidea is derived from the family Phymatoceratidae of the Hildoceratoidea, beginning with the Hammatoceratidae near the end of the Early Jurassic.
References
- ^ Paleobiology Database Hammatoceratoidea entry
- ^ Arkell, W.J.; Kummel, B.; Wright, C.W. (1957). Mesozoic Ammonoidea. Treatise on Invertebrate Paleontology, Part L, Mollusca 4. Lawrence, Kansas: Geological Society of America and University of Kansas Press.
- ^ D.T. Donovan et al 1981. Classification of Jurassic Ammonitina. The Ammonoidea. Systematics Association special volume 18.