Calcidiscus leptoporus - phase change from HOL to HET
Coccolithophores mostly reproduce asexually by simple binary cell-division. But sexual reproduction does occasionally occur and is marked by production of haploid daughter-cells covered by holococcoliths. Following fusion of two daughter-cells, a diploid cell is produced and the coccolith type reverts to heterococcolith. This award-winning image provides rare documentation of this process, as the diploid cell with its cover of heterococcoliths (in pink) emerges from within the cover of the fused daughter-cells (in green). See also the separate figure explaining the life-cycle.

Details: Specimen from the Alboran Sea, western Mediterranean (R/V Hesperides cruise Mater II, station 69).
Filename: 124-10.jpg
Credits (collecter and image):