''Rugoconites'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

Ediacaran biota The Ediacaran (; formerly Vendian) biota is a Taxonomy (biology), taxonomic period classification that consists of all life forms that were present on Earth during the Ediacaran Period (). These were composed of enigmatic tubular and frond-sh ...

found as

fossils A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in ...

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

tentacle In zoology, a tentacle is a flexible, mobile, and elongated organ present in some species of animals, most of them invertebrates. In animal anatomy, tentacles usually occur in one or more pairs. Anatomically, the tentacles of animals work main ...

s. The bifurcating radial ribs, spreading from a central dome, serve to distinguish this

from the

sponge Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate through t ...

Palaeophragmodictya ''Palaeophragmodictya'' is an extinct genus of sponge-grade organisms from the Ediacaran Period. Originally interpreted as a hexactinellid sponge, the organism also bears some coelomate characteristics, including bilateral symmetry. Morphology ...

'', and may represent the channels of the

gastrovascular The gastrovascular cavity is the primary organ of digestion and circulation in two major animal phyla: the Coelenterates or cnidarians (including jellyfish and corals) and Platyhelminthes (flatworms). The cavity may be extensively branched into ...

system. Fossils of ''Rugoconites'' have been interpreted as early

s, although this is countered by Sepkoski ''et al.'' (2002), who interpreted the organism as a free-swimming jellyfish-like

cnidaria Cnidaria () is a phylum under kingdom Animalia containing over 11,000 species of aquatic animals found both in freshwater and marine environments, predominantly the latter. Their distinguishing feature is cnidocytes, specialized cells that th ...

n; similar to '' Ovatoscutum''. 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 Symmetry (from grc, συμμετρία "agreement in dimensions, due proportion, arrangement") in everyday language refers to a sense of harmonious and beautiful proportion and balance. In mathematics, "symmetry" has a more precise definit ...

and be a member of the

Trilobozoa ''Trilobozoa'' (meaning "three-lobed animals") is a phylum of extinct mobile animals that were originally classified into the Cnidaria. The basic body plan of ''Trilobozoa'' is often a tri-radial or radial sphere-shaped form with lobes radiating ...

. ''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. However, due to the dubious nature of R. tenuirugosus, its taxonomy is still unclear, and it has been suggested that a new genus named ''Wadea'' should be erected for ''''R." tenuirugosus''. In 1966,

Martin Glaessner Martin Fritz Glaessner AM (25 December 1906 – 23 November 1989) was a geologist and palaeontologist. Born and educated in the Austro-Hungarian Empire, he spent the majority of his life in working for geoscientific institutes in Austria, Russia ...

along with

Mary Wade Mary Wade (17 December 1775 – 17 December 1859) was a British woman and convict who was transported to Australia when she was 13 years old. She was the youngest convict aboard , part of the Second Fleet. Her family grew to include five gener ...

unearthed the external mould of a form which possessed a small central disc that had eleven radiating lobes from its centre that they named ''Lorenzinites rarus''. This form was also compared to the top of some ''Rugoconites'' specimens. The fossil of ''Lorenzinites rarus'' was, however, reconsidered to be a ''Rugoconites enigmaticus'' specimen despite his original observations and placed it along with the genus in the synonymy of ''Rugoconites''. The genus was then forgotten about and needs further examination.

References

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External links

* http://www.yuzonakano-secretmemory.com/life3.c.html contains a low-quality image. {{Taxonbar, from=Q3942574 Trilobozoa species described in 1966 species described in 1992 Ediacaran Ediacaran life Enigmatic prehistoric animal genera

See also

References

External links