Emiliania huxleyi coccosphere. Image Ruth Eriksen, courtesy AAD EMU.

Emiliania huxleyi coccosphere. Image Ruth Eriksen, courtesy AAD EMU.

Calcidiscus leptoporus coccosphere, Image Ruth Eriksen, courtesy AAD EMU.

Calcidiscus leptoporus coccosphere (partially broken), Image Ruth Eriksen, courtesy AAD EMU.

Coccospheres of Heliscosphaera carteri (left), Coccolithus pelagicus (right) and Emiliania huxleyi (bottom right, partially behind C. pelagicus). Image Ruth Eriksen, courtesy AAD EMU.

Planktonic foraminifera. Image Ruth Eriksen, courtesy AAD EMU.