Fossil group

Coccoliths

Microflora & algae · Triassic – Recent

Microscopic calcite plates, only a few microns across, shed in large numbers by single-celled marine algae (coccolithophores). Countless coccoliths settle to the sea floor to build chalk and deep-sea ooze, and because the producing species evolved rapidly they are important index microfossils for Mesozoic and Cenozoic marine strata.

A broad fossil group rather than a single taxon — the units below record it among their fauna or flora.