Two new orthothecids from the Cambrian of the Barrandian area (Hyolitha, Skryje-Týřovice Basin, Czech Republic)

Abstract

Two orthothecid hyoliths Probactrotheca briketa new genus and new species and Circotheca smetanai new species are described from the Middle Cambrian Buchava Formation of the Skryje-Tyrovice Basin in the Czech Republic. The new forms are based on about twenty well-preserved external and internal moulds of opercula and conchs.

The stratigraphic range and geographic distributions for both taxa are well known.

Keywords

• hyolith
• orthothecids, Circotheca, Probactrotheca