Journal of

GEOsciences

  (Formerly Journal of the Czech Geological Society)

Original Paper

Žítt

Cyathidium Steenstrup (Crinoidea) in the Upper Cretaceous of Bohemia (Czech Republic)

Journal of the Czech Geological Society, volume 41 (1996), issue 3-4, 233 - 239

Two thecae from the upper Cenomanian and 37 from the lower Turonian nearshore sediments are herein described as Cyathidium aff. depressum Sieverts. Furthermore, several conspecific first primibrachials (IBr1) and first secundibrachials (IIBr1) closely resembling those of the Danian species C. holopus were found. Several specimens of Cyathidium aff. depressum show they lived cemented to the organic debris of the bottom. They frequently overgrew smaller cementing associates such as the bryozoans, corals and thecideans. Thecae were also encrusted both during the crinoids' life and postmortally. In the latter case they were mostly colonized by rapidly growing opportunists (agglutinated foraminifers, bryozoans). Some other taphonomic features of Cyathidium and their environmental context are also discussed.