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Most of the specimens ofMyoscolex atelesGlaessner, 1979, the most abundant soft-bodied taxon in the Big Gully fauna from the Lower Cambrian Emu Bay Shale of South Australia, preserveonlythe phosphatized trunk muscles, in striking contrast to the organic residues that characterize other Burgess-Shale-type biotas. This is the oldest phosphatized muscle tissue and the first thus far reported from the Cambrian. The extent of phosphatization implies a source in addition to the animal itself, and this is reflected in high levels of phosphate in the Big Gully sequence compared to other shales. The apparent anomaly posed by the extensive preservation of labile muscle tissue as opposed to the more decay resistant cuticle is explained by the role of bacterial processes in the preservation of soft tissues. New specimens ofMyoscolexreveal a variable number of trunk somites with possible tergites, and flap-like appendages. There is evidence for at least three eyes on the head, and a proboscis may have been present. An annelid affinity is rejected andMyoscolexis reinterpreted as anOpabinia-likeanimal with possible affinities with the arachnomorph arthropods.

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The new, large, frondose and stalked, Ediacaran (late Neoproterozoic) 'petalonamid' Pambikalbae hasenohrae gen. et sp. nov. is preserved in a three-dimensional manner within sandy channel fills occurring directly below the Ediacara Member of the Rawnsley Quartzite on the 'Nilpena' pastoral property at a western outlier of the Flinders Ranges, South Australia. Pambikalbae hasenohrae was made up of numerous chambered vanes supported by a tapering axial stem and an anchoring stalk. Chambers forming the vanes were commonly infilled with sediment, though variably flattened; groups of vanes representing individual specimens can extend as much as c. 3.7 cm deep through the hosting sandstone matrix. Several series of chambers present in each vane abut at zigzag sutures. Pambikalbae is clearly not a cnidarian sea pen, but nevertheless exhibits characteristics suggestive of an evolutionary grade comparable to that of known modern cnidarian divisions. Though the serial geometric configuration of its thin integument seems ideally suited to house symbiotic microbial photoautotrophs, our appraisal of the palaeoecology of Pambikalbae is supportive of its being a heterotrophic suspension feeder. Pambikalbae may plausibly be a highly derived hydrozoan, part of the ancestral stock of the Siphonophorida, or a sister group to the early Chondrophorina.

Nedin, C. 1991 01 15: The dietary niche of the extinct Australian marsupial lion: Thylacoleo carnifex Owen. Lethaia, Vol. 24. pp. 115–118. Oslo. ISSN 0024–1164. Ever since the first systematic descriptions of the extinct Australian marsupial lion. Thylacoleo carnifex (Marsupialia: Thylacoleonidae). by the famous palaeontologist Sir Richard Owen in 1859. controversy has surrounded its dietary niche. This controversy, fuelled by the unique dentition of T. carnifex. with its huge, trenchant, third premolars prompted the suggestion of a variety of dietary niches. In order to ascertain the actual niche, the bones of various adult marsupials. including Thylacoleo. Thylacinus (the marsupial tiger), Marcropus and Sthenurus. were analysed for strontium and zinc. The results show a close correlation between Thylacoleo, Thylacinus and the insectivorous bandicoot Perameles. indicating a carnivorous diet for Thylacoleo, whilst confirming the leaf‐eating niche of Sthenurus. Also, the results confirm the usefulness of strontium bone analysis in ascertaining palaeodietary information whilst showing the value of a divariant over a monovariant analysis. Thylacoleo, palaeodiet. strontium, zinc.