title: NITZSCHIA ALICAE SP. NOV. AND N. PURIFORMIS SP. NOV., NEW DIATOMS FROM EUROPEAN RIVERS AND COMPARISON WITH THE TYPE MATERIAL OF N. SUBLINEARIS AND N. PURA(1).
abstract: Nitzschia sublinearis Hustedt and N. pura Hustedt are common oligosaprobic freshwater diatom species that frequently occur in diatom inventories, thus being important in water quality studies. Both are considered as species with overlapping diagnostic criteria in several floras, which is typical of the whole genus Nitzschia. The type material of Hustedt of N. sublinearis and N. pura was examined using LM and EM in order to document the range of variation within the type populations and to compare it with populations occurring in different European rivers. Detailed observations allowed recognition of two new freshwater diatom species: N. alicae sp. nov., occurring in mesotrophic up to eutrophic conditions, and N. puriformis sp. nov., mostly occurring in oligotrophic habitats, both in rivers and streams at middle and high altitudes. The most reliable taxonomic features that separate both new species from the most similar taxa are the density of fibulae and striae, valve shape, and valve width as well as the shape of areolae. Morphological examination of different populations indicates that N. puriformis is relatively common in European rivers and has been overlooked to date and confounded with N. pura by several researchers. By contrast, N. alicae has, to date, been collected only in Slovakia and Northern Italy, but with a high frequency of occurrence and sometimes in high abundance at sites.
authors.affiliation: Department of Environment and Agro-Biotechnologies (EVA), Public Research Centre - Gabriel Lippmann, 41 rue du Brill, L-4422 Belvaux, Luxembourg Water Research Institute, National Reference Laboratory for Waters, Nabr. L. Svobodu 5, SK-81249 Bratislava, SlovakiaDepartment of Ecology, University of León, E-24071 León, SpainDipartimento di Biologia Animale e dell'Uomo, Università degli Studi di Torino, I-10123 Torino, ItalyDepartament d'Ecologia, Universitat de Barcelona, Av. Diagonal 645, E-08028 Barcelona, Spain Department of Environment and Agro-Biotechnologies (EVA), Public Research Centre - Gabriel Lippmann, 41 rue du Brill, L-4422 Belvaux, Luxembourg.
authors.forename: Daša
authors.initials: D
authors.lastname: Hlúbiková
authors.affiliation: Department of Environment and Agro-Biotechnologies (EVA), Public Research Centre - Gabriel Lippmann, 41 rue du Brill, L-4422 Belvaux, Luxembourg Water Research Institute, National Reference Laboratory for Waters, Nabr. L. Svobodu 5, SK-81249 Bratislava, SlovakiaDepartment of Ecology, University of León, E-24071 León, SpainDipartimento di Biologia Animale e dell'Uomo, Università degli Studi di Torino, I-10123 Torino, ItalyDepartament d'Ecologia, Universitat de Barcelona, Av. Diagonal 645, E-08028 Barcelona, Spain Department of Environment and Agro-Biotechnologies (EVA), Public Research Centre - Gabriel Lippmann, 41 rue du Brill, L-4422 Belvaux, Luxembourg.
authors.forename: Saúl
authors.initials: S
authors.lastname: Blanco
authors.affiliation: Department of Environment and Agro-Biotechnologies (EVA), Public Research Centre - Gabriel Lippmann, 41 rue du Brill, L-4422 Belvaux, Luxembourg Water Research Institute, National Reference Laboratory for Waters, Nabr. L. Svobodu 5, SK-81249 Bratislava, SlovakiaDepartment of Ecology, University of León, E-24071 León, SpainDipartimento di Biologia Animale e dell'Uomo, Università degli Studi di Torino, I-10123 Torino, ItalyDepartament d'Ecologia, Universitat de Barcelona, Av. Diagonal 645, E-08028 Barcelona, Spain Department of Environment and Agro-Biotechnologies (EVA), Public Research Centre - Gabriel Lippmann, 41 rue du Brill, L-4422 Belvaux, Luxembourg.
authors.forename: Elisa
authors.initials: E
authors.lastname: Falasco
authors.affiliation: Department of Environment and Agro-Biotechnologies (EVA), Public Research Centre - Gabriel Lippmann, 41 rue du Brill, L-4422 Belvaux, Luxembourg Water Research Institute, National Reference Laboratory for Waters, Nabr. L. Svobodu 5, SK-81249 Bratislava, SlovakiaDepartment of Ecology, University of León, E-24071 León, SpainDipartimento di Biologia Animale e dell'Uomo, Università degli Studi di Torino, I-10123 Torino, ItalyDepartament d'Ecologia, Universitat de Barcelona, Av. Diagonal 645, E-08028 Barcelona, Spain Department of Environment and Agro-Biotechnologies (EVA), Public Research Centre - Gabriel Lippmann, 41 rue du Brill, L-4422 Belvaux, Luxembourg.
authors.forename: Joan
authors.initials: J
authors.lastname: Gomà
authors.affiliation: Department of Environment and Agro-Biotechnologies (EVA), Public Research Centre - Gabriel Lippmann, 41 rue du Brill, L-4422 Belvaux, Luxembourg Water Research Institute, National Reference Laboratory for Waters, Nabr. L. Svobodu 5, SK-81249 Bratislava, SlovakiaDepartment of Ecology, University of León, E-24071 León, SpainDipartimento di Biologia Animale e dell'Uomo, Università degli Studi di Torino, I-10123 Torino, ItalyDepartament d'Ecologia, Universitat de Barcelona, Av. Diagonal 645, E-08028 Barcelona, Spain Department of Environment and Agro-Biotechnologies (EVA), Public Research Centre - Gabriel Lippmann, 41 rue du Brill, L-4422 Belvaux, Luxembourg.
authors.forename: Lucien
authors.initials: L
authors.lastname: Hoffmann
authors.affiliation: Department of Environment and Agro-Biotechnologies (EVA), Public Research Centre - Gabriel Lippmann, 41 rue du Brill, L-4422 Belvaux, Luxembourg Water Research Institute, National Reference Laboratory for Waters, Nabr. L. Svobodu 5, SK-81249 Bratislava, SlovakiaDepartment of Ecology, University of León, E-24071 León, SpainDipartimento di Biologia Animale e dell'Uomo, Università degli Studi di Torino, I-10123 Torino, ItalyDepartament d'Ecologia, Universitat de Barcelona, Av. Diagonal 645, E-08028 Barcelona, Spain Department of Environment and Agro-Biotechnologies (EVA), Public Research Centre - Gabriel Lippmann, 41 rue du Brill, L-4422 Belvaux, Luxembourg.
authors.forename: Luc
authors.initials: L
authors.lastname: Ector
keywords: Bacillariaceae; Nitzschia; biogeography; diatoms; new species; taxonomy; type material