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 sltiformiss p. n., Stenocrinus raricostatus
sp. n., and Urushicrinus perbellus sp. n.
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