Comment on “An enigmatic, possibly chemosymbiotic, hexactinellid sponge from the early Cambrian of South China”

possibly chemosymbiotic, hexactinellid Decumbispongia yuani on six specimens (five are pictured) from the Hetang Forma-tion of Anhui and the Niutitang Formation of Guizhou, South China. The fossils are three-dimensionally preserved, semi-to-roid, rounded in cross-section (variously compressed), slightly tapering towards one or both ends, and weakly ribbed, bearing irregularly clustered, poorly preserved, orthogonal to diagonal hexactine-based spicule impressions on their surface. The authors correctly reject a possibility that this fossil can be remains of an agglutinating organism bearing detrital spic-ules due to its more or less regular spicule arrangement. At the same time, they emphasise that Decumbispongia differs from intact sponges (common in both formations), by its three-di-mensional rather than strongly flattened preservation and by the fact that spicules are usually pyritised or preserved as externa