Phytoplankton diversity during the spring bloom in the northwestern Mediterranean Sea

Abstract

The section of the Liguro-Provencal basin north of the Balearic Islands is one of the most productive sites in the whole Mediterranean Sea, with intense phytoplankton bloom lasting about 2 months in late winter-early spring. The phytoplankton species composition of the area was investigated using light and electron microscopy to analyze bottle and net samples collected at several stations in spring 2000 and 2003. Serial dilution cultures established from bottle samples were also examined. A total of 168 phytoplankton taxa was identified, consisting of 73 Coscinodiscophyceae, 47 Dinophyceae, 25 Coccolithophyceae and 4 Prymnesiophyceae, 5 Prasinophyceae, 3 Chrysophyceae, 2 Cryptophyceae, 2 Dictyochophyceae, 1 Euglenophyceae, 1 Pelagophyceae, 1 Choanoflagellidea, 1 Filosea and 3 incertae sedis. We also provided a brief taxonomic description and original micrographs for 25 of the smallest and/or less known species identified in the study area, which may go undetected during routine microscopical analysis of fixed samples. Among these, 10 species were recorded for the first time in the Mediterranean Sea, confirming the need of detailed studies to reveal the biodiversity and biogeography of Mediterranean phytoplankton.

Seasonal changes in phytoplankton on the north-eastern shelf of Kangaroo Island (South Australia) in 2012 and 2013

“…In spite of their low contribution worldwide Cryptophyta can occasionally account for major proportion of phytoplankton communities in the Southern Ocean (Buma et al, 1992;Detmer and Bathmann, 1997;Rodriguez et al, 2002) Teleaulax acuta are the most representative Cryptophyta in other oceans. Plagioselmis prolonga and Teleaulax acuta were previously found in the north-western Mediterranean Sea (Percopo et al, 2011), and Plagioselmis and Hemiselmis species were the dominant Cryptophyta in the western Mediterranean Sea (Novarino, 2005) and the Gulf of Naples (Cerino and Zingone, 2006). Moreover 18S rRNA gene sequences from Teleaulax sp.…”

Role of light and photophysiological properties on phytoplankton succession during the spring bloom in the north-western Mediterranean Sea

“…However, slower DES kinetics was observed in the pre-bloom condition (experiment 1), when diatoms were equally dominant. This discrepancy might be explained by the temporal succession of different species of diatoms from the first to the second experiment [36]. We argue that the environmental conditions concurring to the bloom development have selected those species being able to quickly acclimate to varying conditions (i.e.…”

Coupling physics and biogeochemistry thanks to high resolution observations of the phytoplankton community structure in the North-Western Mediterranean Sea

“…Pico-and nanoeukaryotes were distinguished in six cytometric groups based on their scattering (FWS) and fluorescence (FLR and FLO) properties, although pico-and nanoeukaryotes include cells of several taxa (Simon et al, 1994;Worden and Not, 2008;Percopo et al, 2011). As mentioned in Sect.…”

“…NanoHighFLO cells had mean ESD lower than 5 µm. In North-Western Mediterranean Sea, 25 according to the abundant literature, the 2-10 µm size fraction is composed, in importance, of diverse genera of Coscinodiscophyceae (Arcocellulus : 3.5-8.7 μm, Minidiscus : 2.7-4.3 μm, Thalassiosira : 2.7-16.3 μm), Dinophyceae (Heterocaspa : 7.0-10.6 μm), Coccolithophyceae (Anthosphaera : 2.9 μm, Gephytocapsa : 4.7-8.3 μm), Prymnsiophyceae (Chrysochromulina : 3.2-4.0 μm) (Percopo et al, 2011). Small nanoflagelattes dominate the nanophytoplankton size group in terms of cell concentrations most of the year in oligotrophic Mediterranean 30 Sea waters (Siokou-Frangou et al, 2010).…”