陕南寒武系宽川铺组具多级四分体细胞结构的微体化石

MICROSCOPIC FOSSILS WITH MULTI-LEVEL TETRAD CELL STRUCTURES FROM THE CAMBRIAN KUANCHUANPU FORMATION IN SOUTHERN SHAANXI

我国华南扬子板块埃迪卡拉纪—寒武纪的含磷地层中产有丰富的呈现分裂特征的多细胞球状化石。由于有效信息的缺乏,长期以来,这些球状化石的生物属性及分类存在争议。我们在陕南寒武系宽川铺组获得的一些保存精美的分裂型球状化石,具有明显的多级四分体结构,通过与同层位产出的动物卵裂期胚胎化石、瓮安生物群中四分体结构的藻类化石对比,结果表明这些分裂球形化石很可能为多细胞藻类。

A large number of multieellular spherical microfossils occur in the phosphorus-bearing strata from the Ediacaran-Cambrian in South China, in which some of the large multicellular spherical fossils are characterized by cell cleavage. The affinity and classification of these spherical fossils have been controversial for a long time due to thelack of effective anatomical information. Here we report exceptional spherical and non-spherical fossils characterized by specific multi-level, tetrad cell structures from the Kuanchuanpu Formation in southern Shaanxi. These spherical fossils are likely akin to multicellular algae in comparison with co- occurred animal embryos in the cleavage stage and algal fossils with tetrad structures from the Ediacaran Weng＇an biota in South China.