Radiation of Meso-Neoproterozoic and Early Cambrian protists inferred from the microfossil record of China

Abstract

Marine protists can be affected by and reflect changes in the ecological environment. Based on available microfossil evidence from late Mesoproterozoic–Early Cambrian rocks of China, radiations of protists and related changes in ecological environments are discussed in the paper. Remarkable development of protists had occurred by as early as the Mesoproterozoic. Protist diversity significantly decreased in the middle Neoproterozoic due to disruption of the ecological environment that may have been caused by global glaciations. The Doushantuo microfossil assemblage records high diversity and radiation of protists during the early to middle Ediacaran. An acritarch assemblage of Asteridium– Comasphaeridium–Heliosphaeridium–Megathrix, which is contemporaneous with the lowermost Meishucunian small shelly fossil assemblage — Anabarites trisulcatus–Protohertzina anabarica, is widely distributed in the lowermost Cambrian strata of South China and the Tarim Basin and is useful for biostratigraphic correlation with Baltica and other areas.