Bellerophontida

Taxobox
name = Bellerophontida
fossil_range = Late Cambrian - Triassic
regnum = Animalia
phylum = Mollusca
classis = Gastropoda
ordo = Bellerophontida
ordo_authority = Ulrich & Scofield, 1897
subdivision_ranks = Families
subdivision = See text.

Bellerophontida or Bellerophontina are an order of extinct, possibly snail-like molluscs, which first appeared in the very late Cambrian period and continued through to the Triassic period.

Representative genera include "Sinuites", "Euphemetites", "Warthia", "Tetranota", "Bucanopsis", "Tremanotus", "Bellerophon", "Knightites", and many others.

Unlike normal gastropods, the shells of Bellerophonts are characterised by a completely planispiral pattern of coiling, such as one finds in shelled cephalopods. Experts disagree whether Bellerophontids should be classified as torted gastropods or as untorted Tergomya, or whether the group Bellerophontida is perhaps an artificial construct, consisting of a number of distinct groups of Palaeozoic molluscs which evolved the same type of spiral shell independently.

Families

* Bellerophontidae
* Cyrtolitidae
* Sinuopeidae
* Sinuitidae
* Tropidodiscidae

References

* Knight, J. B., Cox, L. R., Keen, A. M., Batten, R. L., Yochelson, E. L., and Robertson, R. (1960). Systematic descriptions [Archaeogastropoda] . In Moore, R. C. (ed.) Treatise on Invertebrate Paleontology. Part I. Mollusca 1, pp. 169-310. Geological Society of America and Kansas University Press, Colorado and Kansas.
* Wagner, P. J. 2001 Gastropod phylogenetics: progress, problems and implications. "Journal of Paleontology" 75: 1128 - 1140

External links

* [http://www.palaeos.com/Invertebrates/Molluscs/Gastropoda/Tergomya/Bellerophontida.html - Palaeos]
* [http://pjw3.fmnh.org/GastroTaxonomy.html Systematic Paleontology of the Earliest Gastropods (Including Family and Genus Level Stratigraphic Ranges and Synonyms) - Peter J. Wagner]