Bellerophon (genus)

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Bellerophon
Temporal range: Silurian–Early Triassic
Bellerophon umbilicalis.jpg
Bellerophon sp.[citation needed]
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda or Monoplacophora
Superfamily: Bellerophontoidea
Family: Bellerophontidae
Subfamily: Bellerophontinae
Genus: Bellerophon
Montfort, 1808

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

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

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

Shell description[edit]

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[edit]

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[edit]

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

Discussion of the taxonomy[edit]

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[edit]

Species within the genus Bellerophon include:

subgenus Bellerophon

subgenus ?

References[edit]

  1. ^ Bouchet P.; Rocroi J.-P.; Frýda J.; Hausdorf B.; Ponder W.; Valdés Á. & Warén A. (2005). "Classification and nomenclator of gastropod families". Malacologia: International Journal of Malacology. Hackenheim, Germany: ConchBooks. 47 (1-2): 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.

Further reading[edit]

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

External links[edit]