Original paper

Biodiversity and biogeographical implications of silica-scaled chrysophytes (Chrysophyceae and Synurophyceae) of the northeast wetlands of Argentina

Vigna, María S. Siver


Wetlands and water bodies in the Paraná Delta River and Iberá System of northeast Argentina were studied for scaled chrysophytes. The Delta region of the Paraná River is composed of a series of braided channels, streams and lagoons that extend over 17,500km2. Although the Delta is situated in the temperate zone, it experiences a more subtropical climate. The water ways of the Iberá System consist of interconnected ponds, lagoons, and creeks covering approximately 12,000 km2. Twenty sites were sampled and their physico-chemical data measured. Twenty-seven species belonging to the genera Spiniferomonas, Paraphysomonas, Chrysosphaerella, Chrysodidymus, Mallomonas and Synura were recorded and in all cases the geographical distribution of these taxa were significantly expanded. A new variety, Mallomonas pseudocratis var. deltaensis, is described. Lastly, the colorless flagellate Gyromitus disomatus was found to be abundant in sites from Iberá.


wetlandschrysophytesbiodiversitybiogeographymallomonasparanadelta riveribera systemargentina.