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Farm Aar also bears domal structures – sedimentary structures that may represent a new form of biologically influenced soft-sediment deformation. Both forms are also associated with membrane-like and bag-like structures. It is likely that the three-dimensional form of these organisms was preserved by the early lithification of surrounding sediment as a result of the precipitation of pyrite in association with bacterial metabolism.

Ernietta is also preserved in transported deposits, but can be found on Aar in original life position, where fossils have been buried more gradually by mud. Pteridinium is preserved within event beds, above scours where massive sand has been deposited and within waning (but still upper flow regime) flows depositing sand laminae. Both of these organisms are found in Nama-style preservation – a taphonomy in which soft-bodied organisms are preserved three-dimensionally in sands and muds. Ernietta was a sac-shaped organism with the same offset symmetry along a suture at the base of the sac, where sets of parallel tubes meet each other. This double-layer of tubes is also found in Ernietta. The vanes are relatively thin and made up of parallel tubes, which are arranged in double-layers. There is a distinctive offset symmetry along this axis where the vanes meet. It is tri-symmetric around the central axis. It had a rubbery, semi-rigid consistency evidenced by the fact that it will bend, but does not fold or tear except at distinct points of weakness. Pteridinium was an elongate, three-vaned organism. These two forms are incompletely characterised in the literature. This site has produced a large number of fossils of Ernietta plateauensis and Pteridinium simplex. Farm Aar in Namibia contains a sequence of rocks from the late Ediacaran Nama Group.

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