Findings of phototrophic picoplankton in the meso- and bathy-pelagic zone of the Ionian sea (Mediterranean).

In the framework of NEMO Project, two multidisciplinary surveys were performed in a deep-sea area in front off Cape Passero (Ionian Sea). Coccoid cyanobacteria, genus Synechococcus and an unidentified group of very small red fluorescing cells were repeatedly observed in the aphotic zones. The cellular abundances were in the order of 103 cells ml-1. Generally the highest concentrations were detected in the epipelagic zone, but significant abundances were achieved also in the meso- and/or bathypelagic zones.