Carinolithidae fam. nov., Carinolithes bohemicus sp. nov. and Slehoferites slehoferi gen. et sp. nov. – new hyolithid taxa from the Bohemian middle Cambrian (Skryje-Týřovice Basin, Czech Republic)

摘要

The hyoliths Slehoferites slehoferi gen. et sp. nov. and Carinolithes bohemicus sp. nov. are described from carbonatic nodules and shale at different stratigraphic levels within the middle Cambrian Buchava Formation of the Skryje-Týřovice Basin in the Czech Republic. Carinolithes bohemicus sp. nov. may be distinguished by a slightly dorsally curved conch with three longitudinal rounded ridges forming a distinct keel on the dorsum and by a platyclaviculate operculum with broad clavicles with their distal ends open, whereas the defining traits of Slehoferites slehoferi gen. et sp. nov. are a conch with a slightly rounded triangular cross-section, distinct muscle scar on the ligula and a platyclaviculate operculum with an almost circular outline and with broadly diverging cardinal processes clavicles (about 40 degrees for clavicles) with a cone cavity below each clavicle. Both taxa are combined under the new family Carinolithidae which differs from other hyolithid families in having a dorsum with developed keel-like ridges, faily long ligula, and a platyclaviculate operculum with distinct and broadly diverging cardinal processes.