Stenothecidae is an extinct family of fossil univalved Cambrian molluscs which may be either gastropods or monoplacophorans.

Stenothecidae
Temporal range: Lower Cambrian – Mid Cambrian[1]
Scientific classification
Kingdom:
Phylum:
Class:
Superfamily:
Family:
Stenothecidae

Runegar & Jell, 1980[2]
Genera

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The name of this taxon should not be confused with that of the class Stenothecoida, a group of problematic Cambrian invertebrates that have a bivalved (dorsal and ventral) shell.[1]

Morphology

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The group comprises conical laterally compressed shells that may be smooth or ornamented with folds or ribs.[3] The shells are broadly limpet-like, which led to their initial consideration as monoplacophoran molluscs.[1]

Taxonomy

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The taxonomic position of the group is unclear;[4] it has been classified as a Yochelcionelloid or Helcionelloid.[5] It is not obviously in the stem group of any modern molluscan class, and has been referred to the monoplacophora,[3] although the monoplacophora are no longer considered to be a clade, and thus that classification means little more than "primitive mollusc".[6]

Genera

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The family Stenothecidae consists of two subfamilies and the following genera:

References

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  1. ^ a b c Yochelson, E. L. (1969). "Stenothecoida, A Proposed New Class of Cambrian Mollusca". Lethaia. 2: 49–62. doi:10.1111/j.1502-3931.1969.tb01250.x.
  2. ^ Runegar & Jell. 1980. Alcheringa, 4(2): 111.
  3. ^ a b Runnegar, B.; Pojeta Jr, J. (Oct 1974). "Molluscan Phylogeny: the Paleontological Viewpoint". Science. 186 (4161): 311–317. Bibcode:1974Sci...186..311R. doi:10.1126/science.186.4161.311. JSTOR 1739764. PMID 17839855.
  4. ^ 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.
  5. ^ a b Parkhaev P. Yu. 2001. Molluscs and siphonoconchs. In: Alexander E. M. et al. (eds.) The Cambrian biostratigraphy of the Stansbury basin, South Australia. Transactions of the Paleontological Institute, Russian Academy of Sciences, 282: 133–210, plates 24–54. Watsonellinae on the page 187.
  6. ^ Budd, G. E.; Jensen, S. (2000). "A critical reappraisal of the fossil record of the bilaterian phyla". Biological Reviews of the Cambridge Philosophical Society. 75 (2): 253–95. doi:10.1111/j.1469-185X.1999.tb00046.x. PMID 10881389.
  7. ^ (in Russian) Missarzhevsky. (after 10 July) 1989. Drevneishie skeletnye okamenelosti i stratigrafiia pogranichnykh tolshch Dokembriia i Kembiia. (English translation: Oldest skeletal fossils and stratigraphy of Precambrian and Cambrian boundary beds.) Trudy Geologicheskogo Instituta, Akademia Nauk SSSR, 443, 237 pp., 32 plates. Mellopegmidae is on the page 179.
  8. ^ Grabau A. W. 1900. Palaeontology of the Cambrian terranes of the Boston Basin. Occasional Papers of the Boston Society of Natural History 4:601–694.

Further reading

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