Parvancorina

Parvancorina
Temporal range: Ediacaran — 558–555 Ma
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Schematic reconstructions of P. sagitta and P. minchami
Scientific classification
Kingdom: Animalia
Phylum: incertae sedis: Arthropoda?
Genus: Parvancorina
Glaessner 1958[1]
Type species
P. minchami
Glaessner 1958
Species
  • P. minchami Glaessner, 1958
  • P. sagitta Ivantsov, 2004 [2]
Part of a series on
The Cambrian explosion
Fossil localities
Key organisms
Ediacara biota
Burgess-type
Small shelly fauna
Evolutionary concepts
Trends
Themes

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Parvancorina is a genus of shield-shaped Ediacaran fossils. It has a raised ridge down the central axis of symmetry. This ridge can be high in unflattened fossils. At the 'head' end of the ridge there are two quarter circle shaped raised arcs attached. In front of this are two nested semicircular lines. Teeth seem to come from the raised parts pointing into the centre spaces. These may show as raised lines. The fossils are normally about 1 cm in each of width and length, but can be up to 2 cm. The fossil is found mainly on the White Sea Coast, Russia.

Parvancorina has compared with the Skania fragilis from the Burgess Shale Biota, Canada, and Primicaris larvaformis from the Chengjiang Biota, China is the Cambrian trilobite-like arthropods.[3][4] However, Parvancorina growth form is unusual for an arthropod,[5][6] and its apparent mode of life appears to rebut an arthropodan affinity.[7]

The organisms typically lived with their "heads" parallel to the current direction,[8] although overfolding of the fossils from all sides contradicts any form of stalked attachment to the sea floor.[7]

See also

List of Ediacaran genera

References

  1. ^ Glaessner, M. F. (1958). "New Fossils from the Base of the Cambrian in South Australia". pp. 185–188. http://www.samuseum.sa.gov.au/Journals/TRSSA/TRSSA_V081/TRSSA_V081_p185p188.pdf. 
  2. ^ Ivantsov, A.Y.; Malakhovskaya, Y.E., Serezhnikova, E.A. (2004). "Some Problematic Fossils from the Vendian of the Southeastern White Sea Region". Paleontological Journal 38 (1): 1–9. http://www.vend.paleo.ru/pub/Ivantsov_et_al_2004_eng.pdf. 
  3. ^ Lin, J. P.; Gon, S.M.; Gehling, J.G.; Babcock, L.E.; Zhao, Y.L.; Zhang, X.L.; Hu, S.X.; Yuan, J.L.; Yu, M.Y.; Peng, J. (2006). "A Parvancorina-like arthropod from the Cambrian of South China". Historical Biology 18 (1): 33–45. doi:10.1080/08912960500508689.  edit
  4. ^ Glaessner, M. F. (1980). "Parvancorina - an Arthropod from the Late Precambrian Fauna of the Ediacara Fossil Reserve". Records of the South Australia Museum 13: 83–90. http://www.biologiezentrum.at/pdf_frei_remote/ANNA_83_0083-0090.pdf. 
  5. ^ Ivantsov A. Yu.; E. B. Naimark (2007). "Ontogenetic variability in the late Vendian problematics Parvancorina Glaessner, 1958". The Rise and Fall of the Vendian (Ediacaran) Biota. Origin of the Modern Biosphere. Transactions of the International Conference on the IGCP Project 493, August 20–31, 2007, Moscow.. Moscow: GEOS. pp. 13–18. http://www.geosci.monash.edu.au/precsite/docs/workshop/moscow07/transaction.pdf. 
  6. ^ Naimark, E. B., Ivantsov A. Yu. (2009). "Growth variability in the late Vendian problematics Parvancorina Glaessner". Paleontological Journal 43 (1): 12–18. doi:10.1134/S003103010901002X. http://www.springerlink.com/content/l82561783464g554/fulltext.pdf. 
  7. ^ a b Paterson, John (2010). International Palaeontology Congress. London. 
  8. ^ Droser, Mary L.. "Anchors away: Anatomy of an Ediacaran sea floor dominated by Parvancorina". Geological Society of America: Abstracts with Programs 39 (6): 332. http://gsa.confex.com/gsa/2007AM/finalprogram/abstract_131751.htm. 

External links