Discosphaera tubifera
The coccoliths produced here are trumpet-shaped. The actual cell is very small in comparison to the coccoliths. The cell diameter is close to the length of the coccolith, the coccolith is produced inside the cell with its base folded, which causes considerable stretching for the cell.

Details: Specimen from the Alboran Sea, western Mediterranean (R/V Hesperides cruise Mater II, station 69).
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