Aquatic Sciences Meeting, Albuquerque 2001
| SS41 Diversity in the Plankton: Patterns & Mechanisms at Different Scales (Spatial and Temporal Connections) |
| Date: Thursday, February 15, 2001, Time: 3:00:00 PM |
| Location: Dona Ana |
| Cros, L, , Institut de Cičncies del Mar. CSIC, Barcelona, Spain, lluisa@icm.csic.es |
| Estrada, M, , Institut de Cičncies del Mar.CSIC, Barcelona, Spain, marta2icm.csic.es |
| HOLO-HETEROCOCCOLITHOPHORID LIFE CYCLES: AN ECOLOGICAL STRATEGY? |
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| Forty years ago, culture experiments showed that Coccolithus pelagicus and Crystallolithus hyalinus, two morphologically very different coccolithophorids, were phases of the same species. Recent findings, in field samples, of combination coccospheres containing both holococcoliths and heterococcoliths suggest that holo-heterococcolithophorid transitions may be a widespread feature in the life cycle of coccolithophorids. This communication presents the results of a SEM study of the distribution of coccospheres in the Catalano-Balearic Sea (NW Mediterranean), during two cruises carried out in summer of 1996. In total, 96 coccolithophorid taxa were recorded including, among others, the pair Helicosphaera carteri and Syracolithus catilliferus, which appear to be, respectively, heterococcolithophorid and holococcolithophorid stages of the same species. In general, holoccolithophorids and heteroccolithophorids presented a segregated vertical distribution pattern in the water column. Holococcolithophorids tended to appear above 30 m depth, in the nutrient-poor but well illuminated waters of the upper euphotic zone, while heterococcolithophorids preferred deeper layers. These data are discussed in relationship with the life cycles and ecological strategies of these organisms. |
| This Session Listing |
