Hildoceratoidea
| Hildoceratoidea Temporal range: early Middle Jurassic | |
|---|---|
 | |
| Harpoceras | |
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Cephalopoda |
| Subclass: | †Ammonoidea |
| Order: | †Ammonitida |
| Suborder: | †Ammonitina |
| Superfamily: | †Hildoceratoidea Hyatt, 1867 |
| Families | |
Hildoceratoidea, formerly Hildocerataceae, is a superfamily of compressed or planulate ammonites, some tending to develop acute outer rims; generally with arcuate or sigmoidal ribs. Aptichus were found in place are double-valved.[2]
Hildoceratoidea is an upper Lower- to lower Middle Jurassic group belonging to the Ammonitina that unites the Hildoceratidae, Hammatoceratidae, Graphoceratidae, and Sonniniidae.[2] In some taxonomies the name Phymatoceratidae is substituted for the Hammatoceratidae[3]
Hildoceratidae, which is the ancestral family, is derived from the Acanthopleuroceratinae, a subfamily in the Eoderoceratacean family, Polyorphitidae. The Stephanocerataceae, Perisphinctaceae, and Haplocerataceae have their source in the Hammitoceratidae which is derived from the Hildoceratidae .[2]
References
- ↑ Kovács, Z.; Géczy, B. (2008). "Upper Toarcian – Middle Aalenian (Jurassic) Erycitinae SPATH (Ammonitina) from the Gerecse Mts, Hungary" (PDF). 125th Anniversary of the Department of Palaeontology at Budapest University – A Jubilee Volume Hantkeniana 6: 57–108.
- 1 2 3 Arkell et al, Treatise on Invertebrate Paleontology, Part L Ammonoidea, (1956)
- ↑ Taxonomicon(Hildocerataceae)|