Bellerophontidae

The Bellerophontidae are an extinct family of specialized globose bellerophontids, Paleozoic and early Triassic mollusks of the class Gastropoda.[2]

Bellerophontidae
Bucanopsis leda (subfamily Bucanopsinae)
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda (?)
Order: †Bellerophontida
Superfamily: †Bellerophontoidea
Family: †Bellerophontidae
McCoy, 1852[1]
Subfamilies and genera

see text.

Geological range

These mollusks appeared in the Late Cambrian and continued until the Early Triassic.

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 these possibly were active, fast-moving molluscs.

Taxonomy

1960 taxonomy

Knight et al. 1960 in the Treatise on Invertebrate Paleontology[3] consider the Bellerophontidae a very large family made up of a number of subfamilies and tribes.

The 1960 classification places the family Bellerophontidae in the order Bellerophontida Ulrich & Scofield, 1897.

The classification presented is:

Order Bellerophontida Ulrich & Scofield, 1897

  • Family Bellerophontidae McCoy, 1851
    • Subfamily Tropidodiscinae Knight, 1956
    • Subfamily Bucaniinae Ulrich & Scofield, 1897
    • Tribe Bucaniides Ulrich & Scofield, 1897
    • Tribe Salpingostomatides Koken, 1925
    • Subfamily Carinaropsinae Ulrich & Scofield, 1897
    • Subfamily Pterothecinae Wenz, 1938
    • Subfamily Bellerophontinae McCoy, 1851
    • Subfamily Knightitinae Knight, 1956

2001 taxonomy

Recently, Peter J. Wagner presented cladograms which divide this assemblage into a number of different groups, as well as combining the Bellerophontidae with the family Sinuitidae.[4] while Bouchet & Rocroi (2005)[2] places Sinuitidae as a family in superfamily Bellerophontoidea.

2005 taxonomy

The taxonomy of the Gastropoda by Bouchet & Rocroi, 2005[2] categorizes Bellerophontidae like this:

Bouchet & Rocroi, on page 271 (2005),[2] also state that the assignation of "symmetrical univalved mollusks "bellerophonts" either to Gastropoda or to Monoplacophora or Tergomya is controversial." In other words, it is not yet certain whether bellerophonts are in fact real gastropods, they might be monoplacophorans or they might belong to a group (Tergomya) that is closely related to the gastropods, but not actually gastropods.

Genera

Genera in the family Bellerophontidae include:[2]

  • subfamily Bellerophontinae
    • genus Bellerophon Montfort, 1808 - type genus of the subfamily Bellerophontinae
  • subfamily Bucanopsinae
    • genus Bucanopsis Ulrich, 1897 - type genus of the subfamily Bucanopsinae
  • subfamily Cymbulariinae
    • genus Cymbularia Koken, 1896 - type genus of the subfamily Cymbulariinae
  • subfamily Knightitinae
    • genus Knightites Moore, 1941 - type genus of the subfamily Knightitinae

other genera include:

  • Aglaoglypta
  • Liljevallospira
  • Pharkidonotus
  • Prosoptychus
  • Ptychobellerophon
  • Ptychosphaera

References
  1. McCoy F. 1852. A synonpsis of the classification of the British Palaeozoic rocks, with a systematic description of the British Palaeozoic fossils in the Geological Museum of the University of Cambridge with figures of the new and imperfectly known species. Parker & Son, London, 661 pp., 25 plates. Bellerophontidae is at page 307.
  2. Bouchet P. & Rocroi J.-P. (Ed.); Frýda J., Hausdorf B., Ponder W., Valdes A. & Warén A. 2005. Classification and nomenclator of gastropod families. Malacologia: International Journal of Malacology, 47(1-2). ConchBooks: Hackenheim, Germany. ISBN 3-925919-72-4. ISSN 0076-2997. 397 pp. http://www.vliz.be/Vmdcdata/imis2/ref.php?refid=78278
  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.

Further reading
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