Bellerophon (genus)

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Bellerophon is a genus of extinct paleozoic marine molluscs of uncertain position (Gastropoda or Monoplacophora) in the family Bellerophontidae.

Bellerophon
Temporal range: Silurian–Early Triassic
Bellerophon umbilicalis.[citation needed]
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda (?)
Order: Bellerophontida
Family: Bellerophontidae
Genus: Bellerophon
Montfort, 1808
Synonyms

Carinaropsis (Bellerophon) (alternative spelling)

The genus was named after Bellerophon, the ancient Greek hero.

Bellerophon is the type genus of the family Bellerophontidae.[1]

Shell description

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The genus is characterised by a shell which is globose, convolute, and planispiral (symmetrically coiled). The shell of Bellerophon superficially resembles that of a miniature cephalopod (e.g. Nautilus or an ammonite), except that septa are lacking.

The shell of Bellerophon is often a couple of centimeters in maximum dimension. The external surface is smooth, ornamented only by growth lines. There is a low crest or ridge running along the midline of the shell.

Many specimens of Bellerophon show something resembling a "waterline" about halfway up the shell, suggesting that a large amount of the mantle and foot were exposed and covered the outside of the shell, as in the extant Cypraeidae and Naticidae.

Possible life habits

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These animals were probably quick moving (for gastropods), relying on speed to avoid predators and, when this was not possible, withdrawing deeply into the shell.[2]

Range of distribution

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The genus occurs worldwide, and is known from the Silurian to the Early Triassic periods.[3]

Taxonomy

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Although usually classified as a primitive gastropod, there is a minority view that the Bellerophontida actually represented a more primitive, untorted type of mollusk, (see Torsion) which evolved a spiral shell independently. Another view is that some Bellerophontids, including Bellerophon, were torted gastropods, but that others were untorted forms.[4]

Species

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Species within the genus Bellerophon include:

subgenus Bellerophon

subgenus ?

References

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  1. ^ Bouchet, Philippe; Rocroi, Jean-Pierre; Frýda, Jiri; Hausdorf, Bernard; Ponder, Winston; Valdés, Ángel & Warén, Anders (2005). "Classification and nomenclator of gastropod families". Malacologia. 47 (1–2). Hackenheim, Germany: ConchBooks: 1–397. ISBN 3-925919-72-4. ISSN 0076-2997.
  2. ^ Linsley R. M. 1978. Locomotion rates and shell form in the gastropoda. Malacologia 17, 193-206, page 201.
  3. ^ Knight J. B., Cox L. R., Keen A. M., Batten R. L., Yochelson E. L. & 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.
  4. ^ Wagner P. J. 2001. Gastropod phylogenetics: progress, problems and implications. Journal of Paleontology 75: 1128 - 1140. page 1130.
  5. ^ a b Gordon, Mackenzie, Jr. & Yochelson, Ellis L. 1987. Late Mississippian gastropods of the Chainman Shale, west-central Utah. 112 pp.
  • P. D. de Montfort. 1808. Conchyliologie systématique, et classification méthodique des coquilles; offfrant leurs figures, leur arrangement générique, leurs descriptions caractéristiques, leurs noms; ainsi que leur synonymie en plusieurs langues. Coquilles univalves, cloisonnées 1

Further reading

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  • Moore, R.C., Lalicker, C.G., and Fischer, A. G., 1952, Invertebrate Fossils, McGraw Hill Book Company, New York; 766 pp.
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