Conulariids and Sphenothallus (Cnidaria, Medusozoa) from the Tonggao Formation (Lower Ordovician, China)

Conulariella sp. and possibly one other conulariid species occur in close association with Sphenothallus sp. in the lower part of the early Floian Tonggao Formation near the town of Sandu, Guizhou Province, China. This is the only known occurrence of Conulariella in Early Ordovician rocks outside of Bohemia (Perunican terrane), and also the first report of Sphenothallus from the Ordovician of China. The apertural margin of Conulariella appears to have been mostly straight, and apertural lappets probably were not present in this genus. Some Tonggao conulariids may have attached to orbiculoid brachiopods in life. Based on the most recent palaeogeographical reconstructions of Gondwana and associated terranes, Conulariella could have had a dispersal path along the Gondwanan margin.