Rugoconites

Rugoconites is a genus of Ediacaran biota found as fossils in the form of a circular or oval-like impression preserved in high relief, six or more centimeters in diameter. The fossils are surrounded by frills that have been interpreted (Wade 1972) as sets of tentacles. The bifurcating radial ribs, spreading from a central dome, serve to distinguish this genus from the sponge Palaeophragmodictya, and may represent the channels of the gastrovascular system.[1] Fossils of Rugoconites have been interpreted as early sponges,[2] although this is countered by Sepkoski et al. (2002), who interpreted the organism as a free-swimming jellyfish-like cnidarian; similar to Ovatoscutum.[3] However, the fossil is consistently preserved as a neat circular form and its general morphology does not vary, therefore a benthic and perhaps slow-moving or sessile lifestyle is more likely. Ivantstov & Fedonkin (2002), suggest that Rugoconites may possess tri-radial symmetry and be a member of the Trilobozoa.[4]

Rugoconites
Temporal range: Ediacaran
Reconstruction of Rugoconites, an extinct organism
Scientific classification
Kingdom: Animalia
Phylum: Trilobozoa
Genus: Rugoconites
Glaessner & Wade 1966
Species
  • R. enigmaticus (type) Glaessner & Wade 1966
  • R. tenuirugosus Wade 1972
Synonyms
  • Lorenzinites rarus Glaessner & Wade 1966
  • Wadea tenuirugosus(?) Jenkins 1992
Artists interpretation of Rugoconites

Rugoconites have been reported in clusters; this may represent a social/colonial way of life, or simply accumulation by the action of currents, sea-floor processes, or possibly preservational conditions.

The Rugoconites genus may contain two species: Rugoconites enigmaticus and Rugoconites tenuirugosus, the latter being less dome-shaped and having smaller and more numerous radial ridges than the former.[5] However, the taxonomy of R. tenuirugosus is still unclear, and it has been suggested that a new genus, named Wadea, should be erected for ''R." tenuirugosus.[6]

See also

References

  1. Fedonkin, M. A.; Cope, J. C. W.; Whittington, Harry Blackmore; Morris, S. Conway (1985-10-17). "Precambrian metazoans: the problems of preservation, systematics and evolution". Philosophical Transactions of the Royal Society of London. B, Biological Sciences. 311 (1148): 27–45. doi:10.1098/rstb.1985.0136.
  2. Gehling, James G.; Rigby, J. Keith (March 1996). "Long expected sponges from the Neoproterozoic Ediacara fauna of South Australia". Journal of Paleontology. 70 (2): 185–195. doi:10.1017/S0022336000023283. ISSN 0022-3360.
  3. Sepkoski, J.J.; Jablonski, D. (2002). ""A Compendium of Fossil Marine Animal Genera"". Bulletins of American Paleontology.
  4. Ivantsov, Andrei Yu; Fedonkin, Mikhail A. (2002). "Conulariid–like fossil from the Vendian of Russia: a metazoan clade across the Proterozoic/Palaeozoic boundary". Palaeontology. 45 (6): 1219–1229. doi:10.1111/1475-4983.00283. ISSN 1475-4983.
  5. "Rugoconites". Ediacaran.org.
  6. Lipps, Jere H.; Signor, Philip W. (2013-11-21). Origin and Early Evolution of the Metazoa. Springer Science & Business Media. ISBN 978-1-4899-2427-8.
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