Discovery of Byronia Mathew,1899 from the Tsinghsutung Formation (Qiandongian Series,Cambrian) in Balang Village of Jianhe County,Guizhou Province,China

The Tsinghsutung Formation(Qiandongian Series,Cambrian) of Songshan Section near Balang village,Jianhe County,Guizhou Province is mainly composed of mudstone and limestone,interbeded by mudstone and limestone at the upper part and topped by middle layer of grayand dolomite.The upper part of Tsinghsutung Formation is rich in Redlichiaids,Ptychopariids,Oryctocephalids,soft-body fossils and other phyla.So far only 1 species,Byronia cf.annulata Liu,1986 has been found in the middle and middle-upper part of Tsinghsutung Formation.The Byronia fossils described in this paper are well preserved and even the transverse ridges on the wall tube can be identifiable.These fossils not only enrich the assemblage of Tsinghsutung Formation biota,but also provide new materials for taphonomy,as well as the systematic evolution of the Early Cambrian Byronia’s in China.