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A previously unrecognized megascopic organic record of textured organic surfaces (TOS), accompanies the iconic body fossils of the Ediacara biota in assemblages around the globe. Paleoecological analysis of successive bedding planes of strata, from the late Ediacaran Rawnsley Quartzite in the Flinders Ranges of South Australia, reveals that certain distinctive TOS elements represent the most common organic features in the Ediacara biota. The TOS consist of patterned assemblages of textured mats, and simple tubular, spicular and globular body fossils. The TOS morphotypes are discrete but are characterized by variable spatial dimensions; some surfaces are completely covered with a particular TOS while others are on the order of square centimeters. Well known Ediacara body fossils, while striking for their distinctive body plans and dominating some of the beds, are relatively minor components of bedding assemblages in most cases. TOS are likely a result of a range of grades of organisms from microbial grade to possibly metazoan.
Many elements of TOS have previously been misdiagnosed as trace fossils. In practice, the trace fossil record is limited to at most three morphotypes that indicate the presence of bilaterian animals. Although TOS represent a simpler grade of organismic construction than the discrete and more complex Ediacara body fossils, they were preserved in a similar manner. The record of TOS rapidly wanes after the onset of deep burrowing at the base of the Cambrian.
TOS without its larger elements is also a feature where body fossils are unknown, in a wider range of paleoenvironmental settings in Ediacaran siliciclastic successions in Australia, Namibia and western North America. Therefore TOS is a useful megascopic indictor of the degree of benthic biological activity in facies where stromatolites and microfossils are not preserved.
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