The hexactinellid sponge Cyathophycus from the Lower Ordovician Klabava Formation of the Prague Basin, Czech Republic

Abstract

A unique cluster of pentactine spicules has been observed in the lower part of the Olešná Member of the Klabava Formation (Upper Tremadocian or earliest Floian) in the Prague Basin. Some 100 pentactines of uniform size are arranged in one layer of regular quadrules. Although the general shape of the sponge is not preserved, the orientation of the pentactines in the quadrules is consistent with attribution to Cyathophycus Walcott, 1879.