''Pilbaria'' is a genus of fossil

stromatolite Stromatolites ( ) or stromatoliths () are layered Sedimentary rock, sedimentary formation of rocks, formations (microbialite) that are created mainly by Photosynthesis, photosynthetic microorganisms such as cyanobacteria, sulfate-reducing micr ...

-forming cyanobacteria from the

Paleoproterozoic The Paleoproterozoic Era (also spelled Palaeoproterozoic) is the first of the three sub-divisions ( eras) of the Proterozoic eon, and also the longest era of the Earth's geological history, spanning from (2.5–1.6 Ga). It is further sub ...

era 2.3 to 1.7 billion years ago. It is named after the

Pilbara The Pilbara () is a large, dry, sparsely populated regions of Western Australia, region in the north of Western Australia. It is known for its Indigenous Australians, Aboriginal people; wealth disparity; its ancient landscapes; the prevailing r ...

region of

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where the

type specimen In biology, a type is a particular wikt:en:specimen, specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally associated. In other words, a type is an example that serves to ancho ...

was found.

Description

The type species, ''Pilbaria perplexa'' is characterised by long, mostly straight, subparallel and mostly smooth columns with proportionately small transversely elongate niches with projections. Near the bases of beds, branching varies from parallel to markedly divergent, but above that level, it is α-β-parallel or slightly divergent. Laminae are predominantly steeply convex and form a patchy wall. ''Pilbaria'' is similar to '' Inzeria'' and ''

Nordia Nordia () is a moshav shitufi in central Israel. Located in the Sharon plain near Netanya and the HaSharon Junction, it falls under the jurisdiction of Lev HaSharon Regional Council. In it had a population of . History In 1926 the American ...

'' in that it has well-developed niches and projections.

Distribution and age

Fossils of ''P. perplexa'', the type species, have been found in the Wyloo Group of the Pilbara region in Western Australia, aged 1.7 to 2 billion years old. It has also been found in the Epworth Group of the Coronation and Pine Creek

Geosyncline A geosyncline (originally called a geosynclinal) is an obsolete geology, geological concept to explain orogeny, orogens, which was developed in the late 19th and early 20th centuries, before the theory of plate tectonics was envisaged.#Sengor1982, ...

s in

Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...

, aged 1.865 to 2.2 and 2 to 2.3 billion years old. ''P. boetsapia'' and ''P. inzeriaformis'' are from Schmidtsdrift Formation of the

Northern Cape Province The Northern Cape ( ; ; ) is the largest and most sparsely populated province of South Africa. It was created in 1994 when the Cape Province was split up. Its capital is Kimberley. It includes the Kalahari Gemsbok National Park, part of the Kga ...

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...

, aged approximately 2.2 billion years old. ''P. deverella'' is from the Yelma and Frere formations of the Earaheedy Group of the Nabberu Basin in Western Australia. It is the youngest of the four species, with fossils from these areas aged to about 1.7 billion years old. Other stromatolite genera found in the Yelma formation include '' Ephyaltes'', '' Externia'', '' Murgurra'' and '' Yelma''.

References

Proterozoic life Prehistoric bacteria Cyanobacteria genera Fossil taxa described in 1972 {{cyanobacteria-stub

Description

Distribution and age

See also

References