A team of Chinese and German researchers have discovered the world's oldest fossils of Rossellids, pushing forward the history of similar sponge fossils by more than 300 million years.

The group of 440 million-year-old sponge fossils was found in eastern China's Anhui Province by Li Lixia from the Nanjing Institute of Geology and Palaeontology under the Chinese Academy of Sciences and her colleagues from China and Germany.

The fossils are dated to the uppermost Ordovician. The sponge shows a saccular, globular or oval form with a relatively thick wall.

The discovery gives some tentative insights into the affinity between the new species and other taxa. It represents the oldest record, providing new information for understanding the phylogeny of sponges and on the evolution of modern Hexactinellida, said Li in the paper published on the latest issue of the German Journal of Paleontology (Paleontologische Zeitschrift).

source: Xinhua