''Ediacaria'' is a

fossil 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 ...

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

dating to the Ediacaran Period of the

Neoproterozoic The Neoproterozoic Era is the unit of geologic time from 1 billion to 538.8 million years ago. It is the last era of the Precambrian Supereon and the Proterozoic Eon; it is subdivided into the Tonian, Cryogenian, and Ediacaran periods. It is prec ...

Era. Unlike most Ediacaran biota, which disappeared almost entirely from the fossil record at the end of the Period, ''Ediacaria'' fossils have been found dating from the Baikalian age (850–650 Ma) of the Upper Riphean to 501

million years ago The abbreviation Myr, "million years", is a unit of a quantity of (i.e. ) years, or 31.556926 teraseconds. Usage Myr (million years) is in common use in fields such as Earth science and cosmology. Myr is also used with Mya (million years ago) ...

, well into the Cambrian Period. ''Ediacaria'' consists of concentric rough circles, radial lines between the circles and a central dome, with a diameter from 1 to 70 cm.

Systematics and taxonomy

''Ediacaria'' was named by

Reg Sprigg Reginald Claude Sprigg, (1 March 1919 – 2 December 1994) was an Australian geologist and conservationist. At 17 he became the youngest Fellow of the Royal Society of South Australia. During 1946, in the Ediacara Hills, South Australia he di ...

in 1947, after the

Ediacara Hills Ediacara Hills are a range of low hills in the northern part of the Flinders Ranges of South Australia, around north of the state capital of Adelaide. The hills are known for being the location of significant fossils, and have given their nam ...

South Australia South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ...

. Two species are recognised: ''E. flindersi'', described by Sprigg from the Pound

Quartzite Quartzite is a hard, non- foliated metamorphic rock which was originally pure quartz sandstone.Essentials of Geology, 3rd Edition, Stephen Marshak, p 182 Sandstone is converted into quartzite through heating and pressure usually related to tec ...

in the Ediacara Hills, and ''E. booleyi'', described in 1995 from a

Late Cambrian Late may refer to: * LATE, an acronym which could stand for: ** Limbic-predominant age-related TDP-43 encephalopathy, a proposed form of dementia ** Local-authority trading enterprise, a New Zealand business law ** Local average treatment effect, ...

deposit at Booley Bay ( County Wexford),

Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...

. The species were named after the

Flinders Ranges The Flinders Ranges are the largest mountain range in South Australia, which starts about north of Adelaide. The ranges stretch for over from Port Pirie to Lake Callabonna. The Adnyamathanha people are the Aboriginal group who have inhabit ...

and Booley Bay, respectively. ''Ediacaria'' is possibly a synonym for '' Aspidella terranovica'' described in 1872. Although ''Ediacaria'' is one of the first described organisms from the Precambrian, '' Aspidella'' was described earlier, although its age was not understood to be Precambrian. As ''Aspidella'' is apparently a

form taxon Form classification is the classification of organisms based on their morphology, which does not necessarily reflect their biological relationships. Form classification, generally restricted to palaeontology, reflects uncertainty; the goal of s ...

, ''Ediacaria'' may yet be valid and denote one specific genus among several that seem to make up ''Aspidella''. '' Spriggia wadea'' is quite likely a synonym of ''Ediacaria'' (and consequently, possibly ''Aspidella''); the differences seem to be merely due to different substrate in which the animals were embedded. (Gehling ''et al.'' 2000) ''Ediacaria'' was often classified as a jellyfish (a Scyphozoan

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 ...

n), and has also been interpreted in many of the categories postulated to house the Ediacaran biota. A conspicuous filamentous microstructure preserved in some pyritised specimens suggests that it may have been a microbial colony, which disrupted the surrounding

microbial mat A microbial mat is a multi-layered sheet of microorganisms, mainly bacteria and archaea, or bacteria alone. Microbial mats grow at interfaces between different types of material, mostly on submerged or moist surfaces, but a few survive in deserts ...

to create the distinctive pattern (Grazhdankin, in press).

References

Notes

* (1995): A rigid-bodied Ediacaran biota from Upper Cambrian strata in Co. Wexford, Éire. ''Geological Journal'' 30(2): 89-109. (HTML abstract) * (2000): The first named Ediacaran body fossil, ''Aspidella terranovica''. ''Palaeontology'' 43(3): 427-456. PDF fulltext
* (2001): Microbial origin of some of the Ediacaran fossils. GSA Annual Meeting 2001: Paper 177-0
HTML abstract
* (in press): Lethaia. * (2001): Paleogeographic links between Yreka Terrane (Klamath Mountains, Northern California) and Alaska's Nixon Fork and Alexander Terranes. GSA-

AAPG The American Association of Petroleum Geologists (AAPG) is one of the world's largest professional geological societies with more than 40,000 members across 129 countries as of 2021. The AAPG works to "advance the science of geology, especially as ...

SPE SPE may refer to: Science and technology * Spe (planet), 14 Andromedae b * Serum protein electrophoresis * Solar particle event,generating very high energy protons * Solid phase extraction, from a mixture * Epitaxy#Solid-phase, Solid-phase epitax ...

Meeting 2006: Paper 24-6
HTML abstract
* (1982): Cambrian Medusoids from the St. John Group, southwestern New Brunswick. ''Geological Survey of Canada Current Research Part B.'' 82(1): 71-76. * (1947): Early Cambrian(?) Jellyfishes from the Flinders Ranges, South Australia. ''Transactions of the Royal Society of South Australia'' 71: 212-224
PDF fulltext
* (1960): ''Velumbrella czarnockii'' n. gen., n. sp. - Meduse du Cambrien Inferieur des Monts de Sainte-Croix. ''

Acta Palaeontologica Polonica ''Acta Palaeontologica Polonica'' is a quarterly peer-reviewed open access scientific journal of paleontology and paleobiology. It was established by Roman Kozłowski in 1956. It is published by the Institute of Paleobiology of the Polish Academy ...

'' 5: 337-346. * (2005): A Middle Cambrian age for the Ediacara-type fauna from the Booley Bay Formation, County Wexford, Ireland: new acritarch data and their implications. ''In:'' (eds.): Pre-Cambrian to Palaeozoic Palaeopalynology and Palaeobotany. ''

Carnets de Géologie ''Carnets Geol.'' (previously ''Carnets de Géologie'' or ''Carnets de Géologie - Notebooks on Geology'') is an electronic journal that publishes in the field of geosciences, and particularly paleontology, stratigraphy, and sedimentology. The ope ...

/ Notebooks on Geology'', Memoir 2005/02, Abstract 1
PDF fulltext

External links

* Peripatus Home Page

Version of 2006-MAY-10. Retrieved 2007-JUN-06. {{Taxonbar, from=Q5337989 Ediacaran life Cambrian life Fossils of Australia Scyphozoa Fossil taxa described in 1947

Systematics and taxonomy

See also

References

Notes

External links