''Tappania'' is an acanthomorph

acritarch Acritarchs () are organic microfossils, known from the Precambrian to the present. The classification is a catch all term used to refer to any organic microfossils that cannot be assigned to other groups. Their diversity reflects major ecolog ...

found in late

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 ...

Mesoproterozoic The Mesoproterozoic Era is a geologic era that occurred from . The Mesoproterozoic was the first era of Earth's history for which a fairly definitive geological record survives. Continents existed during the preceding era (the Paleoproterozoic ...

and

Neoproterozoic The Neoproterozoic Era is the last of the three geologic eras of the Proterozoic geologic eon, eon, spanning from 1 billion to 538.8 million years ago, and is the last era of the Precambrian "supereon". It is preceded by the Mesoproterozoic era an ...

rocks. The oldest examples are around 1630 million years old, making them some of the oldest known evidence of

Eukaryotes The eukaryotes ( ) constitute the domain of Eukaryota or Eukarya, organisms whose cells have a membrane-bound nucleus. All animals, plants, fungi, seaweeds, and many unicellular organisms are eukaryotes. They constitute a major group of ...

in the fossil record. * ''Tappania plana'' appears in Paleoproterozoic formations of India ( Deonar) and northern China ( Baicaoping and Beidajian), both with an age of 1,630 mya. It is a roughly spherical acritarch, 30-60 μm in diameter, with one or two small necks. Small branched and / or partitioned tubes emerge from the central body. * ''Tappania'' sp. It appears in deposits of the

in northern Australia, northwestern US and central Siberia, with an age of up to 850 mya and 200-300 mya stratigraphic presence. It is larger than ''Tappania plana'', up to 300 μm in length, with an elongated or lobed central body from where hyphae-like tubular extensions radiate. These hyphae form a three-dimensional network around the central body.

References

{{Taxonbar, from=Q22666148 Acritarch genera Paleoproterozoic Mesoproterozoic Neoproterozoic