Bellerophontidae
From Wikipedia, the free encyclopedia
Bellerophontidae | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
Scientific classification | ||||||||||
|
||||||||||
Subfamilies and Genera | ||||||||||
Subfamily Bellerophontinae:
Subfamily Bucaniinae |
The Bellerophontidae are an extinct family of globose and specialised bellerophonts. These are fossil mollusks with coiled shells, and they are thought to have been gastropods.
Contents |
[edit] Geological range
These mollusks appeared during the Ordovician period and continued through to the Triassic period.
[edit] Shell description
The shell resembles a miniature Nautilus, with greatly overlapping, rounded whorls, in which the last whorl completely encompasses the others, leaving either a very narrow umbilicus on either side, or none at all. At the aperture of the shell is a slit, which results in a sort of low ridge that runs along the length of shell. The shell has a low profile and it is possible that these were active, fast-moving molluscs.
[edit] Taxonomy
Knight et al 1960 in the Treatise on Invertebrate Paleontology consider the Bellerophontidae a very large family made up of a number of subfamilies and tribes. The classification presented is as follows:
- Family Bellerophontidae McCoy 1851
-
- Subfamily Tropidodiscinae Knight 1956
- Subfamily Bucaniinae Ulrich & Scofield 1897
-
- Tribe Bucaniides Ulrich & Scofield 1897
- Tribe Salpingostomatides Koken 1925
Recently Peter Wagner has presented cladograms which divide this assemblage into a number of different groups, as well as combining the Bellerophontidae with the family Sinuitidae.
[edit] 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, Geological Society of America and Kansas University Press, Colorado and Kansas.
- Linsley, R. M. 1978. Locomotion rates and shell form in the gastropoda. Malacologia 17, 193-206
- Moore, R.C., Lalicker, C.G., and Fischer, A. G., (1952), Invertebrate Fossils, McGraw Hill Book Company, New York; 766 pp.
- Wagner, P. J. (2001) Gastropod phylogenetics: progress, problems and implications. Journal of Paleontology 75: 1128 - 1140
- ----- [no date]. Systematic Paleontology of the Earliest Gastropods (Including Family and Genus Level Stratigraphic Ranges and Synonyms
[edit] External links
- Bellerophontida - Palaeos