First discovery of the siliceous sponge spicules from the Middle Triassic Luoping Biota, Yunnan Province

Two types of siliceous sponge spicules have been discovered from Luoping Biota from Yunnan Province, southwest China, including the monaxons and tetractines which contains anatriaene, protriaene and calthrops three forms.The spicules are well-preserved with the micro-structure of axial canal.The spicules are composed of the elements of silicon and oxygen by testing with Energy Dispersive Spectrometer (EDS).The element compositions and the types of the spicules indicate that they belong to the Demospongea.These fossil spicules are the first reported in Luoping Biota, they indicate that the sponges used to live together with other fossils in Luoping Biota, and increasing the diversity of this biota.