Stratigraphic column of the Xiazhen Formation with the 18 stromatoporoid-bearing intervals (clathrodictyid stromatoporoids)

Clathrodictyids are the most abundant stromatoporoids in the Upper Ordovician Xiazhen Formation (middle to upper Katian) of South China. A total of nine species belonging to four clathrodictyid genera are identified in the formation, including Clathrodictyon idense (Webby and Banks, 1976), Clathrodictyon cf. Cl. microundulatum (Nestor, 1964), Clathrodictyon cf. Cl. mammillatum  (Schmidt, 1858), Clathrodictyon megalamellatum Jeon n. sp., Clathrodictyon plicatum (Webby and Banks, 1976), Ecclimadictyon nestori Webby, 1969, Ecclimadictyon undatum (Webby and Banks, 1976), Camptodictyon amzassensis (Khalfina, 1960) and Labyrinthodictyon cascum (Webby and Morris, 1976). The clathrodictyid fauna in the Xiazhen Formation is very similar to those from both New South Wales and Tasmania, although the latter two Australian regions do not share any common clathrodictyid species during the Late Ordovician. The paleobiogeographic pattern indicates that the northward drift of South China resulted in a f...