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The Fezouata Lagerstätte, discovered in the Lower Ordovician rocks of Morocco, is a Konservat‐Lagerstätte of prime scientific importance. It provides access not only to the ‘shelly’ (skeletonized) part of its fossil assemblages, but also to non‐biomineralized to lightly sclerotized organisms and to exceptionally preserved soft tissues of a complex ecosystem, mixing elements of both the ‘Cambrian Explosion’ and the ‘Great Ordovician Biodiversification Event’ (GOBE). The Fezouata Lagerstätte occurs at different intervals in the Fezouata Shale, a formation ranging from the lower Tremadocian to the upper Floian (Lower Ordovician). In spite of recent major advances in the detailed biostratigraphy of the Fezouata Shale, there is currently no consensus on the precise age of the fossiliferous levels yielding exceptionally preserved assemblages. Consequently, all available biostratigraphical evidence based on several fossil groups is here critically reviewed and discussed. It can be concluded that exceptional preservation is restricted to a few thin, discontinuous, lens‐shaped horizons occurring in two distinct parts of the Fezouata Shale: a lower interval (260–330 m above the base of the formation) and an upper interval (570–620 m). Integrated biostratigraphical studies, essentially based on investigations of graptolites, acritarchs and conodonts, indicate that the lower interval can be correlated with the upper Tremadocian, whereas the upper interval corresponds to the middle Floian. [ABSTRACT FROM AUTHOR]

The Bohemo-Iberian regional scale for South Gondwana, involving the 'Mediterranean Province', comprises five regional stages (Arenigian, Oretanian, Dobrotivian, Berounian and Kralodvorian) plus the global Tremadocian and Hirnantian. The predominance of shallow-water taxa in those high-latitude faunas imposes serious difficulties for correlating the regional succession with the formal global chronostratigraphy because of the almost total absence of the key graptolites and conodonts defining the base of the standard series, stages and stage slices. Instead, the abundant benthic faunas (trilobites, brachiopods, molluscs, echinoderms) of South Gondwanan origin largely dominated in the area from the middle Darriwilian to the late Katian. The poleward faunal migration of originally Avalonian, Baltic, Laurentian and even Asiatic taxa during the Boda Event of global warming progressively ends with the endemicity in the region, where the ensuing benthic assemblages were severely affected by the Hirnantian glaciation. The regional scale significantly improves the precision of correlations between Ordovician strata from SW and central Europe, North Africa and a large part of the Middle East. An updated record of palaeontological data from areas where Mediterranean faunas remain practically unknown, or are still poorly investigated, is also included. Palaeobiogeographical relationships based on the distribution of faunas across South Gondwana are suggested as an improvement for positioning many territories in modern palaeogeographical reconstructions and offer a constructive approach to problems related to the pre-Variscan and pre-Alpine orogenic puzzles. [ABSTRACT FROM AUTHOR]

Brachiopods are among the first animal phyla to emerge from the Cambrian Explosion, rapidly diversifying to all major palaeocontinental blocks within 20 million years. The group underwent another steep rise in diversity during the Ordovician, and their relative abundance and diversity made them one of the most successful invertebrate groups during the entire Palaeozoic. During this time, brachiopods lived in a range of environments and represented a significant component of marine ecosystems, yet information regarding their modes of life and ecology is somewhat limited. Recent studies, primarily from the Chengjiang and Burgess Shale Lagerstätten, have revealed that by the Middle Cambrian (Series 3, Stage 5) brachiopods from across the phylum had already developed a range of ecological strategies and life modes. Cambrian brachiopods occupied distinct trophic niches on soft and hard substrates and exhibited at least five types of lifestyles: pedicle attachment, pedicle anchoring, cemented, free‐lying and semi‐infaunal. Comparisons with Ordovician benthic assemblages show that despite the explosion of brachiopod taxa witnessed in the Ordovician, with the exception of the appearance of burrowing brachiopods, life strategies of brachiopods remained largely the same. Indicating that the majority of life modes observed in brachiopods had rapidly evolved and was already in place prior to the Great Ordovician Biodiversity Event. [ABSTRACT FROM AUTHOR]