Middle/Late Devonian phoebodont-based ichthyolith zonation

A subdivision of the upper part of the Devonian (varcus through praesulcata conodont zones) into six ichthyolith zones is proposed. The zonation is based on the stratigraphic ranges of elasmobranch teeth from the pelagic facies of Central and Eastern Europe. Species of the genus Phoebodus were chosen as index taxa. A gap in the zonation in the lowermost Famennian is caused by the temporary absence of phoebodonts on the studied areas. The scarcity of phoebodont remains begins already in the uppermost Frasnian linguiformis zone; and may tentatively be correlated to the Kellwasser event. Two new species of Phoebodus are introduced.