Late Precambrian algal megafossilsChuariaandTawuiain some areas of eastern China

Abstract

Chuaria is widespread in Late Precambrian deposits throughout the world. In China it has been found in the Jingeryu Formation of Jixian County, Tianjin, and in its equivalents in eastern China including the Nanfen Formation of Liaoning and Jilin Provinces, and the Liulaobei Formation of Anhui Province. In the latter, Chuaria is associated with the genus Tawuia which Hofmann (in Hofmann & Aitken, 1979) described as algae of undertermined affinity and which is based on material from Canada. The glauconitic sandstone directly resting upon Chuaria-bearing greyish-green shale of the Jingeryu Formation in Jixian County has a K-Ar age of 0.899 Ga. This paper describes C. circularis Walcott, T. dalensis Hofmann and T. sinensis n. sp., and discusses the morphology, biological and taxonomic affinities, and age and geographic distribution of Chuaria. Because of the association of Chuaria and Tawuia in the Mackenzie Mountains, Canada, and also in the area of Shouxian County, Anhui Province, China, it is considered that Chuaria and Tawuia probably have close affinities. According to their general morphology and occurrence, both may be marine planktonic multicellular algae.