贵州清镇早寒武世早期藻类化石

从贵州清镇阿坝寨震旦系一寒武系界线剖面,寒武系底界附近的燧石岩石薄片中,发现的一种保存很好的藻类化石——一种内部具浓密胶状物质的多细胞球形群体化石。它不同于以往在前寒武纪发现的所有藻类化石,故建新属 Symphysosph(?)era gen.nov.(属型种 Symphy-sosphaera radiaalis gen.et sp.nov.)。文中详细比较了新属和几个已知属的区别及可能的亲缘关系。

A NEW ALGAL FOSSIL FROM EARLY CAMBRIAN IN QINGZHEN COUNTY,GUIZHOU PROVINCE,CHINA

A new algal fossil was collected from the lower part of the Lower Cambrian, a Sinian-Cambrian boundary section in Abazhai of Qingzhen County,Guizhou Province.It was discovered in petrographic thin sections of a black laminated chert.The new fossil,Symphysosphacra radialis gen.et sp.nov.is a fossilized multicellular colony characterized by a surface layer of cells enclosed in an enve- lope,inner cavity permeated with dark dense mucilage embedded with numerous spherical units,hs difference from all morphs discovered in Precambrian,indi- cares that the genus may represent member of a new orde at the beginning of Cambrian.Its stratigraphic and biological significance merits our attantion.