Tappania is a putative eukaryotic microfossil, the type acritarch found in sediments up to 1,630 million years old. Its morphology suggests it is related to the fungus.
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.
The Tappania plana fossils discovered in Montana (USA) are different than those unearthed in China. These fossils suggest the ancient creatures could develop an outer membrane, which could function separately from the original inner membrane.
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 plana may represent one of the earliest eukaryotic fossils.
Tappania plana was first described almost 20 years ago in shale samples from China. This organism acts as a shape-shifter with the ability to grow bulbs and tube-like structures. "If you can create a little ball and a little tube you can think of all the different permutations to change the shape and within that basic capacity you could reshape yourself into almost anything."The Tappania plana fossils discovered in Montana (USA) are different than those unearthed in China. These fossils suggest the ancient creatures could develop an outer membrane, which could function separately from the original inner membrane.
In the Sarda Formation of the Bahraich Group, Ganga Basin (Prasad and Asher,
2001), and possibly in correlative beds of the Kheinjua Group,Vindhyan Basin (Prasad et al.,
2005) in northern India. U-Pb zircon dating of ash beds from the Deonar “Porcellanite”
Formation just below the Vindhyan succession containing unambiguous Tappania indicates
that these fossils are ≤1631 ±1 Ma old (Ray et al., 2002).
2001), and possibly in correlative beds of the Kheinjua Group,Vindhyan Basin (Prasad et al.,
2005) in northern India. U-Pb zircon dating of ash beds from the Deonar “Porcellanite”
Formation just below the Vindhyan succession containing unambiguous Tappania indicates
that these fossils are ≤1631 ±1 Ma old (Ray et al., 2002).
Shuiyousphaeridium macroreticulatum from the Mesoproterozoic Ruyang Group, China. (a) Light microphotograph showing specimen with numerous regularly spaced cylindrical processes that flare outward; (b, c, e–f) SEM images showing (b) whole specimen, with inset showing details of process morphology, (c) outer wall surface covered with ridges that delimit granular polygonal fields, (e) wall reticulation and (f) inner wall surface of closely packed, beveled hexagonal plates; (d) TEM image showing the two appressed walls of a single specimen—note multilayered wall comprising a thick electron-dense homogeneous layer of organic plates (ii) between an outer layer of debris and processes—note base of process at bottom left of centre (iii) and a thin electron-tenuous layer (i) that lines the inner side of plates. Scale bar in a=57 μm for a, 50 μm for b (20 μm for inset), 1.2 μm for c and e, 0.5 μm for d and 2.5 μm for f.
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