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The Late Ordovician Tafilalt Biota of the Moroccan Anti-Atlas includes a diverse range of soft-bodied organisms, including palaeoscolecids, paropsonemid eldonioids, graptolites and cheloniellid arthropods, as well as a rich assemblage of mineralised taxa, among them conulariids, trilobites and echinoderms, often found as articulated skeletons. The new fossil locality, not far from the original Bou Nemrou site, has produced two new palaeoscolecid taxa, the new genus and species Anguiscolex africanus and the new species Wronascolex superstes. They are preserved as compression fossils in fine-grained mudstones, where the original phosphatic sclerites have been diagenetically substituted by pyrite and later weathered to iron oxides, giving them a characteristic rusty colour. This area of Gondwana was located adjacent to the Late Ordovician South Pole and both Anguiscolex africanus gen. et sp. nov. and Wronascolex superstes sp. nov. present a degree of polar gigantism, which has been suggested for other taxa in such high palaeolatitudes such as bryozoans, conulariids, trilobites and radiodonts. Lastly, the occurrence of Wronascolex extends the distribution of this typically Cambrian taxon into the Late Ordovician, indicating a total range for the genus exceeding 60 million years, more than any other palaeoscolecid genus described to date. [ABSTRACT FROM AUTHOR]

The boundaries and subdivisions of the global Dapingian stage cannot be adequately characterized in the extensive south-polar Gondwana continental shelves. Correlatable sediments, dated to some extent by palynomorphs, are generally highly condensed in shale facies ( < 10 m thick) or are entirely lacking, whereas in shallow-water sandstones they may locally reach more than 100 m thick. In the absence of valuable data derived from key macrofossils (graptolites and conodonts), the regional chitinozoan biostratigraphy has gone through numerous conceptual variations in the last 20 years, which has not helped a precise definition of the base of the Dapingian, provisionally included in the “upper” Arenigian regional stage of peri-Gondwana. [ABSTRACT FROM AUTHOR]