Late Cretaceous crinoids (Crinoidea) from Eastern Poland
Salamon, Mariusz; Gorzelak, Przemysław
published: Jun 14, 2010
The description of a diversified Late Cretaceous crinoid fauna from Eastern Poland (Vistula River valley and Podlasie area) is presented. The following taxa were recorded in the Vistula River valley: Isocrinus? sp., Comatulida, Bourgueticrinus sp., Cyrtocrinina (Cenomanian); Isocrinidae, Isocrinus? granosus, Glenotremites paradoxus, Bourgueticrinus sp., Tetracrinus jagti, Cyathidium sp. (Turonian); Isocrinus? sp., I.? granosus, Comatulida, Bourgueticrinus sp., Roveacrininae, Roveacrinus communis (Coniacian); Isocrinus? minutus, Bourgueticrinus sp., B. cf. ellipticus, Hemicrinus marcinowskii n. sp. (Santonian); Austinocrinus bicoronatus, Bourgueticrinus sp., B. brydonei, B. cf. constrictus, B. granulosus, B.? suedicus (Campanian); Isocrinus? sp., Bourgueticrinus sp. (Maastrichtian). The Cretaceous sediments of Podlasie area yielded similar crinoid assemblage [Isocrinus? sp., Comatulida, Bourgueticrinus sp., Marsupites testudinarius (Santonian); Isocrinus? sp., Nielsenicrinus sp., N. carinatus, Comatulida, Bourgueticrinus sp., Phyllocrinidae, Tetracrinus sp., Roveacrininae (Campanian); Isocrinus? sp., Nielsenicrinus sp., Isselicrinus buchii, Comatulida, Bourgueticrinus sp. (Maastrichtian)]. Hemicrinus marcinowskii n. sp. (Cyrtocrinida, Sclerocrinidae) is a Santonian spoon-like, small cyrtocrinid with low, wide bowl shaped cup that is oblique and irregular. The youngest record of the genus Hemicrinus was previously known from the Albian sediments. The presence of cyrtocrinid families (Holopodidae, Phyllocrinidae, Plicatocrinidae or Tetracrinidae) was confirmed in the Upper Cretaceous sediments. These finds constitute the youngest record of the families Phyllocrinidae and Plicatocrinidae [or Tetracrinidae] to date. Comparison of the crinoid variability in the studied units and evolution of Late Cretaceous cyrtocrinids are presented. The present paper discusses also the significance of the Polish Late Cretaceous crinoids for their diversity and disparity in the Middle-Upper Cretaceous. Additionally, taphonomic observations have been conducted. A very high percentage of bite-marks and aberrant growths indicates that predation on stalked crinoids has been intense during the Late Mesozoic.