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Fossils of the Ediacara Biota preserve the oldest evidence for complex, macroscopic animals. Most are difficult to constrain phylogenetically, however, the presence of rare, derived groups suggests that many more fossils from this period represent extant groups than are currently appreciated. One approach to recognize such early animals is to instead focus on characteristics widespread in animals today, for example multicellularity, motility, and axial polarity. Here, we describe a new taxon, Quaestio simpsonorum gen. et sp. nov. from the Ediacaran of South Australia. Quaestio is reconstructed with a thin external membrane connecting more resilient tissues with anterior‐posterior polarity, left‐right asymmetry and tentative evidence for dorsoventral differentiation. Associated trace fossils indicate an epibenthic and motile lifestyle. Our results suggest that Quaestio was a motile eumetazoan with a body plan not previously recognized in the Ediacaran, including definitive evidence of chirality. This organization, combined with previous evidence for axial patterning in a variety of other Ediacara taxa, demonstrates that metazoan body plans were well established in the Precambrian. [ABSTRACT FROM AUTHOR]

A large enigmatic fossil is described from the early Cambrian (Series 2, Stage 3) Heatherdale Shale in the Fleurieu Peninsula, South Australia. It has an almost circular outline about 150 mm across, with an outer rim and 27–30 evenly-spaced rays that extend about two-thirds of the distance to the centre of the structure; it shows radial symmetry. There is a featureless central area with a width about one-third that of the entire specimen. The fossil is preserved as pale-coloured material that stands out slightly above the surrounding mudstone. XRF data indicate that there is little compositional difference between the fossil and the enclosing rock. The fossil may appear to be a transverse section of a larger organism, but it does not continue down into the surrounding rock. This suggests it is a non-mineralised compression fossil that retains the remnants of a three-dimensional structure. Possible affinities with radiodont oral cones, ctenophores, eldonioids, scyphozoa and archaeocyaths are discussed, but no definite assignment can be made. [ABSTRACT FROM AUTHOR]

Cover caption: The cover image is based on the Article A new motile animal with implications for the evolution of axial polarity from the Ediacaran of South Australia by Scott D. Evans et al., https://doi.org/10.1111/ede.12491..By Scott D. Evans; Ian V. Hughes; Emily B. Hughes; Peter W. Dzaugis; Matthew P. Dzaugis; James G. Gehling; Diego C. García‐Bellido and Mary L. DroserReported by Author; Author; Author; Author; Author; Author; Author; Author [Extracted from the article]

Despite the status of the eye as an 'organ of extreme perfection' (1), theory suggests that complex eyes can evolve very rapidly (2). The fossil record has, until now, been inadequate in providing insight into the early evolution of eyes during the initial radiation of many animal groups known as the Cambrian explosion. This is surprising because Cambrian Burgess-Shale-type deposits are replete with exquisitely preserved animals, especially arthropods, that possess eyes (3-5). However, with the exception of biomineralized trilobite eyes, virtually nothing is known about the details of their optical design. Here we report exceptionally preserved fossil eyes from the Early Cambrian (~515 million years ago) Emu Bay Shale of South Australia, revealing that some of the earliest arthropods possessed highly advanced compound eyes, each with over 3,000 large ommatidial lenses and a specialized 'bright zone'. These are the oldest nonbiomineralized eyes known in such detail, with preservation quality exceeding that found in the Burgess Shale and Chengjiang deposits. Non-biomineralized eyes of similar complexity are otherwise unknown until about 85 million years later (6,7). The arrangement and size of the lenses indicate that these eyes belonged to an active predator that was capable of seeing in low light. The eyes are more complex than those known from contemporaneous trilobites and are as advanced as those of many living forms. They provide further evidence that the Cambrian explosion involved rapid innovation in fine-scale anatomy as well as gross morphology, and are consistent with the concept that the development of advanced vision helped to drive this great evolutionary event (8)., The anatomy of many Early and Middle Cambrian (-520-500 million years (Myr) ago) organisms is known in considerable detail from numerous Burgess-Shale-type deposits worldwide (3-5), but the fine structure of [...]

We report the preservation of the eight-armed Ediacara fossil Eoandromeda octobrachiata as carbonaceous compressions in the Doushantuo black shale of south China and as casts and molds in the Rawnsley Quartzite in South Australia. The contrasting preservational styles in two taphonomic windows indicate that E. octobrachiata may have had a relatively recalcitrant organic integument, which rules out its close comparison with giant agglutinated foraminifers such as xenophyophores. Its octaradial symmetry and dextrally spiraling arms suggest that it may be a diploblastic-grade animal sharing some features with cnidarians and ctenophores, although its phylogenetic affinity remains open. It is the first and only unambiguously identified Ediacaran macrofossil that occurs in two drastically different taphonomic windows, thus bridging the conventional biological and taxonomic gaps between the Ediacara and Miaohe biotas, which collectively record the earliest known macroscopic and complex life.

Abstract: The Mistaken Point assemblage of the Ediacara fossils is dominated by rangeomorphs with homologous fractal branching elements. The most distinctive are the fusiform fossils, herein named Fractofusus misrai n.gen., [...]