Unusual sedimentary structures or new fossils from the early Ediacaran Brachina Subgroup, southern Flinders Ranges, South Australia?

Defining a moment in time when metazoan lifeforms initially evolved is a desired outcome within the geological community and the current widely accepted timeline is drawn at ca 580 Ma. This date approximates to the timing of the Gaskiers Glaciation and Acraman Asteroid Impact within the mid Ediacaran Period, yet there is a growing body of evidence that macroscopic organisms existed prior to that time. Fossils discovered within the early Ediacaran-aged Brachina Subgroup (ca 635–586 Ma), throughout and beyond the Flinders Ranges of South Australia, suggest that subgroup to be a stratigraphic interval pivotal to unravelling the history of macroscopic life, at least within the Adelaide Superbasin if not globally. In addition to the occurrence of numerous and widespread sessile cup-shaped and frondose lifeforms within the subgroup, two unusual structures, previously ascribed inorganic origins, may in fact represent either the activity of, or actual fossils of, ancient organisms. These structures involve a possible death assemblage of juvenile cup-shaped Ernietta-like organisms preserved within a gutter and a dendritic fan-shaped impression possibly made by either an endobenthic sediment-displacive organism or fungi.