Abstract
Jurassic (Tithonian) and Lower Cretaceous (Berriasian/Valanginian-Hauterivian) strata of the Vendryně and Cieszyn Limestones formations in the Czech Republic and Poland are locally rich in crinoid remains, consisting of whole cups, isolated cup elements, brachial plates, columnals and pluricolumnals, cirrals, and holdfasts. They are assigned to isocrinids (Isocrinida: Isocrinus cf. amblyscalaris, Isocrinida indet.), cyrtocrinids (Cyrtocrinida: Eugeniacrinites sp., Phyllocrinus sp., Gammarocrinites sp., Hemicrinus tithonicus, Plicatocrinus hexagonus, Cyrtocrinida indet.), millericrinids (Millericrinida: Millericrinida indet.), and thiolliericrinids (Comatulida, Thiolliericrinidae: Thiolliericrinidae gen. et sp. indet.). Late Cretaceous (Maastrichtian) and Paleogene (Paleocene-Oligocene) crinoids from the Subsilesian Unit are recorded as individual remains belonging to: Isocrinida indet., Cyrtocrinida indet., bourgueticrinids (Comatulida, Bourgueticrinina: Bourgueticrinina fam. et gen. indet.) and roveacrinids (Roveacrinida, Roveacrinidae gen. et sp. indet.). Roveacrinids were retrieved only from Maastrichtian samples. Despite the conclusions previously presented that isocrinids of the Outer Flysch Carpathians dominated around the Jurassic-Cretaceous boundary due to the very shallow sedimentary environment of these strata, we can now conclude that they were common and associated with cyrtocrinids in all types of environments. It is also worth mentioning that cyrtocrinids and isocrinids occur in Paleogene sediments that were deposited in extremely shallow environments. On the other hand, many literature data suggested that Cretaceous (by mid-Cretaceous) isocrinids migrated to deep-water areas, as a response to an increase in the number of predators during the so-called Mesozoic marine revolution.
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