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Language: Engilsh with bilingual summary in English and French
The Early Silurian coral recovery fauna of Anticosti Island, eastern Canada, provides important data on the response and evolution of a major group of tropical benthic biota after a time of global stress and multiple Late Ordovician glaciations. This richly fossiliferous tropical carbonate setting, ca. 20º–25º S paleolatitude, spans the time from the beginning of the Silurian (Rhuddanian), to that of the comparable classic fauna of Gotland, Sweden, which was initiated during the late Early Silurian (Telychian). We provide herein the stratigraphic distribution, a summary of the paleoecology, and the taxonomy of the bulk of the Anticosti Llandovery rugose coral fauna, covering 13 families (including one new subfamily, the Strephophyllinae), 27 genera (three of which are new: Cladopaliphyllum, Cormorantia, and Chaloupella), and 39 species (21 of which are new). The highest diversity of colonial rugose corals occurs in four separate reefal settings of the late Aeronian East Point Member, Menier Formation, and mid–late Telychian Chicotte Formation. The mid Telychian Pavillon Member, Jupiter Formation, has the most diverse group of solitary rugosans. Rugose coral faunas in the lowermost Llandovery Becscie Formation of Anticosti consist primarily of relatively rare, small, solitary forms, survivors of the end Ordovician multiple mass extinctions, with colonial species only appearing in the upper Becscie (Chabot Member), from which we describe a single genus and species, Nanophyllum pelagicum (Billings). A significantly diverse rugose coral fauna appears for the first time in the East Point Member (late Aeronian), ca. 2–3 myr after the end Ordovician mass extinction (as it does elsewhere globally). The late Rhuddanian–Telychian rugose coral faunas of Anticosti are primarily cosmopolitan at the generic level.
