Distribution and taxonomic notes of Eunotia Ehrenberg 1837 (Bacillariophyceae) in rivers and streams of Northern Spain

Distribution and taxonomic notes on Eunotia Ehrenberg 1837 (Bacillariophyceae) in rivers and streams of Northern of SpainBetween August and October of 2003, a total of 397 samples of epilithic diatoms were collected from different stations belonging to the control network of the North Hydrographical Confederation of Spain (CHN).One hundred and seventeen sites with Eunotia diatom species were found.Galicia, with 78 localities, was the region with higher representation.Eighteen taxa of the Eunotia genus were identified, 17 of them to the species level.Eunotia minor (Kützing), Grunow in van Heurck and Eunotia implicata Nörpel, Lange-Bertalot & Alles were the most common species, present in 59 % and 50.4 % of the samples, respectively.Conductivity and water acidity were the most important factors in determining Eunotia distribution in the studied area.The main objective of this work was to contribute to the knowledge, from the taxonomic and distribution viewpoints, of the diatoms of the genus Eunotia Ehrenberg that were found in the Iberian Peninsula.It is the first comprehensive study on the Eunotia genus of northern Spain.