关键词: 中寒武世, 海绵骨针, 湖南

Abstract: The newly recovered assemblages of disarticulated sponge spicules are reported, occurring in Middle Cambrian carbonates from Wangcun section, western Hunan, South China. The most abundant kinds of spicules include stauractins, tauactins, triaxon pentactins and pentaxon pentactins. Axial canals can be observed on these well preserved specimens. A highly modified form of pentaxon pentacins is recognized as a new genus-Speciosuspongia, with two new species: Speciosuspongia hunanensis and Speciosuspongia wangcunensis. Speciosuspongia is a bilateral symmetrical siliceous pentaxon pentactin. One ray is bulky and in the symmetrical plane, the other four rays are assorted as two pairs. The bulky ray of Speciosuspongia hunanensis is deformed to a plate, which is interpreted as an important intermediate character between highly modified sponge spicules of Early and Late Cambrian.

Key words: Middle Cambrian, sponge spicules, Hunan