New Machaeridia materials from the Ordovician Miaopo Formation in western Hubei Province
Machaeridia is a poorly-known group of marine animals belonging to Annelida,and is characterized by a tiny,bilaterally symmetrical body.They are relatively rare,but widely distributed,and have been reported from the Ordovician System in Anti-Atlas of Morocco,South China,Tarim and some other regions.This paper reports and de-scribes three specimens of Machaeridia from the Miaopo Formation at the Leizu section in Yuan'an County,Hubei Province.They are identified as Plumulites sp.A and Lepidocoleus sp.This finding expands the temporal and spatial distribution of Machaeridia in South China.These specimens represent the occurrence of Machaeridia in a shallow in-tra-platform depression during the Great Ordovician Biodiversification Event(GOBE).In addition,we discuss the morphological characteristics and classification of the Machaeridia,and propose that the early Paleozoic Machaeridia includes three families:Plumulitidae,Lepidocoleidae and Turrilepadidae.