Revision of two prioniodontid species (Conodonta) from the Early Ordovician Honghuayuan Formation of Guizhou, South China

Abstract

The septimembrate conodonts Acodus triangularis (Ding in Wang, 1993) and Prioniodus honghuayuanensis n.sp., are described and illustrated from Guizhou, South China where both species are widely distributed in Lower Ordovician strata. The adenticulate A. triangularis, which ranges through the middle and upper parts of the Honghuayuan Formation, is morphologically more primitive than the denticulate P. honghuayuanensis, which is present from the uppermost Honghuayuan Formation into the lower part of the succeeding Dawan Formation. Prioniodus honghuayuanensis, elements of which were previously ascribed to Oepikodus communis (Ethington & Clark, 1964), appears to be closely related to a species of Prioniodus from the basal Whiterockian of Utah, North America. © Copyright Australian Museum, 2005.