A new Early Jurassic (ca. 183 Ma) fossil Lagerstätte from Ya Ha Tinda, Alberta, Canada

摘要: Lagerstatten —deposits of exceptionally preserved fossils—offer vital insights into evolutionary history. To date, only three Konservat-Lagerstatten are known from Early Jurassic marine rocks (Osteno, Posidonia Shale, and Strawberry Bank), all located in Europe. We report a new assemblage fossils from Alberta, Canada, the first Konservat-Lagerstatte described from North America. The Ya Ha Tinda assemblage includes articulated vertebrates (fish, ichthyosaurs), crinoids, crustaceans, brachiopods, abundant mollusks (coleoids with soft tissues, ammonites, gastropods, bivalves), wood, microfossils. Paired bioand chemostratigraphies show that Lagerstatte deposition occurred during late Pliensbachian through early Toarcian, capturing the carbon isotope excursion associated Toarcian Oceanic Anoxic Event. Therefore, Panthalassan biota is coeval with Toarcian Tethys Ocean (Posidonia Shale and Strawberry Bank). Comparisons among these deposits permit new insights diversity, ecology, biogeography Jurassic marine communities during time pronounced biological and environmental change (e.g., expanded subsurface anoxia, warming, and extinctions). They also highlight possibility Mesozoic Anoxic Events are temporal foci exceptional preservation.