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...