Hildoceratoidea, formerly Hildoceratacaea, 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.[3]
Hildoceratoidea Temporal range: Early—Middle Jurassic,
| |
---|---|
Harpoceras exaratum | |
Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Cephalopoda |
Subclass: | †Ammonoidea |
Order: | †Ammonitida |
Suborder: | †Ammonitina |
Superfamily: | †Hildoceratoidea Hyatt, 1867 |
Families[2] | |
Hildoceratoidea is an upper Lower to lower Middle Jurassic group belonging to the Ammonitina that unites the Hildoceratidae, Hammatoceratidae, Graphoceratidae, and Sonniniidae.[3] In some taxonomies the name Phymatoceratidae is substituted for the Hammatoceratidae[4]
Hildoceratidae, which is the ancestral family, is derived from the Acanthopleuroceratinae, a subfamily in the Eoderoceratoidean family, Polyorphitidae. The Stephanoceratoidea, Perisphinctoidea, and Haploceratoidea have their source in the Hammatoceratidae which is derived from the Hildoceratidae.[3]
![](http://upload.wikimedia.org/wikipedia/commons/thumb/2/25/Hildoceratoidea.svg/220px-Hildoceratoidea.svg.png)
References
edit- ^ 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. Archived from the original (PDF) on 2011-07-16. Retrieved 2010-11-25.
- ^ "Paleobiology Database - Hildoceratoidea". Retrieved 2017-10-19.
- ^ a b c Arkell et al., Treatise on Invertebrate Paleontology, Part L Ammonoidea, (1956)
- ^ Taxonomicon (Hildocerataceae)|