Rugoconites
From Wikipedia, the free encyclopedia
Rugoconites Fossil range: Ediacaran |
||||||||||
---|---|---|---|---|---|---|---|---|---|---|
Line drawing of Rugoconites fossils, not illustrating the rare "frills".
|
||||||||||
Scientific classification | ||||||||||
|
||||||||||
Species | ||||||||||
|
A member of the Ediacaran biota which takes the form of a circular to oval impression preserved in hyporelief, six or more centimeters in diameter. They are surrounded by a frill that has been interpreted (Wade 1972) as a set of tentacles. The bifurcating radial ribs, spreading from a central dome, serve to distinguish this genus from the very similar Paleophragmodictya, and may represent the channels of the gastrovascular system (Fedonkin & Cope 1985). Speculation that they may represent sponges (Gehling 1996) is not accepted by Sepkoski et al. (2002), who interpret it as a jellyfish-like cnidarian; it's believes that, in common with Ovatoscutum, they were free-swimming (Waggonner 1995). Cnidarian affinities are not necessarily refuted by Ivantstov & Fedonkin (2002), who suggest that Rugoconites may possess tri-radial symmetry and be a member of the Trilobozoa.
Fossil 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 (Droser 2007).
[edit] External links
http://www.yuzonakano-secretmemory.com/life3.c.html contains a low-quality image.
[edit] References
- The Paleobiology database. Retrieved on 2007-08-13.
- Droser, M.L. (2007). "Anchors Away: Anatomy Of An Ediacaran Sea Floor Dominated By Parvancorina". 2007 GSA Denver Annual Meeting.
- Fedonkin, M.A.; Cope, J.C.W. (1985). "Precambrian Metazoans: The Problems of Preservation, Systematics and Evolution [and Discussion]". Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences 311 (1148): 27–45. doi: .
- Gehling, J.G.; Rigby, J.K. (1996-03-01). "Long expected sponges from the Neoproterozoic Ediacara fauna of South Australia". Journal of Paleontology 70 (2): 185–195.
- Ivantstov, A.Y.; Fedonkin, M.A. (2002). "Conulariid-like Fossil From The Vendian Of Russia: A Metazoan Clade Across The Proterozoic/palaeozoic Boundary". Palaeontology 45: 1219–1229. doi: .</ref>
- Sepkoski, J.J.; Jablonski, D.; Foote, M. (2002). "A Compendium of Fossil Marine Animal Genera". Bulletins of American Paleontology 363 (1): 560. Paleontological Research Institution.
- Waggoner, B.M. (1995). "Ediacaran Lichens: A Critique". Paleobiology 21 (3): 393–397.