Abstracts
Abstract
Eight species of isocrinines have been documented from the Lower Cretaceous to Pleistocene of Jamaica. New finds include a second specimen of a Miocene species from central north Jamaica, previously regarded as Diplocrinus sp. but reclassified as Teliocrmus? sp. herein. Extant Teliocrinus is limited to the Indian Ocean, although Miocene specimens have been recorded from Japan, indicating a wider distribution during the Neogene. One locality in the early Pleistocene Manchioncal Formation of eastern Jamaica has yielded three species of isocrinine, Cenocrinus asterius (Linnl), Diplocrinus maclearanus (Thomson) and Neocrinus decorus Thomson. These occur in association with the bourgueticrinine Democrinus sp. or Monachocrinus sp. These taxa are all extant and suggest a minimum depositional depth for the Manchioneal Formation at this locality of about 180 m. This early Pleistocene fauna represents the most diverse assemblage of fossil crinoids docu mented from the Antillean region.
RESUME
Huit especes d'isocrinines de la periodc du Cretace infericur au Pleistocene de la JamaTque ont <tc documented. Les nouvelles decouvertes comprennent un deuxieme specimen d'unc espece du Miocene du nord central de la JamaTque, auparevant considered comme Pespece Diplocrinus, mais reclassified en tant que Teliocrinus? aux presentes. Le Teliocrmus existant est limite a I'ocean Indien, mime si on a releve' des specimens du Miocene au Japon, ce qui est reVilateur d'une distribution plus n£pandue au cours du Neogene. Un emplacement de la formation de Manchioneal du Pleistocene inftrieur dans I'est de la Jamalque a livre trois especes d'isocrinines : le Cenocrinus asterius (Linne), le Diplocrinus maclearanus (Thomson) et le Neocrinus decorus (Thomson). Ceux-ci sont presents en association avec les bourgueticrinines Democrinus ou Monachocrinus. Ces taxons sont tous existants et ils permettent de supposer que la formation de Manchioneal aurait une profondeur minimale de sedimentation d'environ 180 m a cet endroit. Cette faunc du Pleistocene infericur represente Tassemblage le plus diversify de crinoYdes fossiles documents dans la region des Antilles.
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