Crinoid assemblages in the Polish Givetian and Frasnian
Givetian and Frasnian crinoid faunas of the Holy Cross Mts and Silesia-Cracow Region are arranged in fourteen assemblages. Their diversity decreases generally from northern to southern regions reflecting crinoid habitat differentiation during either platform or reef phases of facies development. Distributional patterns are superimposed on a six-step general succession of the faunas which was mainly controlled by environmental changes related to eustatic cycles. Nine crinoid species have been identified by calyces, thirteen species are based on stems attributed to calyx genera, and forty-eight kinds of colurnnals, probably representing distinct species, are classified within artificial supraspecific units. Of them thirteen are new: Anthinocrinus brevicostatus sp. n., Asperocrinus brevispinosus
sp. n., Calleocrinus bicostatus sp. n., Calleocrinus kielcensis sp. n., Exaesiodiscus cornpositus sp. n., Kasachstanocrinus tenuis sp. n., Laudonornphalus pinguicostatus sp. n., Noctuicrinus? varius sp. n., Ricebocrinus parvus sp. n., Schyschcatocrinus delicatus sp, n., Schyschcatocrinus multiformis sp. n., Stenocrinus raricostatus
sp. n., and Urushicrinus perbellus sp. n.
Key words: crinoids, palaeoecology, Devonian, Poland.
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