Fragilaria rinoi sp. nov. (Fragilariales, Fragilariophyceae) from periphytic river samples in Central Portugal

Cristina Delgado, M. Helena Novais, Saúl Blanco, Salomé F.P. Almeida


A new benthic freshwater diatom, Fragilaria rinoi Almeida & C.Delgado sp. nov., is described from river periphyton samples in Portugal. Fragilaria rinoi sp. nov. is illustrated and discussed based on populations collected from the Vouga, Mondego and Lis river basins in central Portugal and compared with the type material of Fragilaria vaucheriae (Kütz.) J.B.Petersen. The morphological features of the new diatom species are documented through light and scanning electron micrographs, including a comparative analysis with related species of the genus (F. candidagilae Almeida, C.Delgado, Novais & S.Blanco, F. intermedia Grunow in Van Heurck, F. neointermedia Tuji & D.M.Williams, F. recapitellata Lange-Bert. & Metzeltin, F. perminuta (Grunow) Lange-Bert., F. vaucheriae and F. microvaucheriae C.E.Wetzel & Ector). Fragilaria rinoi sp. nov. is characterized by solitary cells without spines, lanceolate valves with slightly rostrate apices, a narrow, linear axial area, and a large, unilateral central area.
Fragilaria rinoi sp. nov. may be confused with F. microvaucheriae in terms of length, striae density and outline, although a morphometric analysis revealed that F. rinoi sp. nov. is significantly wider. Fragilaria rinoi sp. nov. is present in rivers with high dissolved oxygen concentrations, medium to high conductivity, neutral to slightly alkaline pH and high mean values of nitrates and ammonium.


diatoms; periphyton; Fragilaria; new species; Portugal; rivers

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Almeida S.F.P. & Gil M.C.P. 2001. Ecology of freshwater diatoms from the central region of Portugal. Cryptogamie, Algologie 22 (1): 109–126.

Anderson M.J. 2001. A new method for non-parametric multivariate analysis of variance. Austral Ecology 26: 32–46.

APHA 1995. Standard methods for the examination of water and wastewater. Ed. 19. American Public Health Association, American Water Works Association, and Water Pollution Control Federation, Washington, D.C.

Cavalier-Smith T. 1995. Zooflagellate phylogeny and classification. Tsitologiia i genetika 37: 1010–1029.

CEN TC230 N68 2003. Water Quality: Guidance for Routine Sampling of Benthic Algae in Shallow Swift Running Waters. Comité Européen de Normalisation, Brussels.

Delgado C., Novais M.H., Blanco S. & Almeida S.F.P. 2015. Examination and comparison of Fragilaria candidagilae sp. nov. with type material of Fragilaria recapitellata, F. capucina, F. perminuta, F. intermedia and F. neointermedia (Fragilariales, Bacillariophyceae). Phytotaxa 231 (1): 1–18.

Dujardin J.P., Kaba D. & Henry A.B. 2010. The exchangeability of shape. BioMed Central Research Notes 3: 1–7.

Feio M.J., Reynoldson T.B., Ferreira V. & Graça M.A.S. 2007. A predictive model for the water quality bioassessment of the Mondego catchment, central Portugal. Hydrobiologia 589: 55–68.

Greville R.K. 1833. Diatomaceae. In: Smith J.E. & Hooker W.J. (eds) The English Flora, vol. 5 (1): 401–415. Longman, Rees, Orme, Brown, Green & Longman, London.

Hammer Ø., Harper D.A.T. & Ryan P.D. 2001. PAST: Paleontological statistics software package for education and data analysis. Palaeontologia Electronica 4: art. 4.

Kelly M.G. & Whitton B.A. 1995. The trophic diatom index: a new index for monitoring eutrophication in rivers. Journal of Applied Phycology 7: 433–333.

Krammer K. & Lange-Bertalot H. 1991. Bacillariophyceae 3. Teil: Centrales, Fragilariaceae,

Eunotiaceae. In: Ettl H., Gerloff J., Heynig H. & Mollenhauer D. (eds) Süßwasserflora von Mitteleuropa, vol. 2. VRG Gustav Fisher Verlag, Jena.

Krammer K. & Lange-Bertalot H. 2004. Bacillariophyceae 3. Teil: Centrales, Fragilariaceae, Eunotiaceae. Ergänzte und korrigierte 2. Auflage. In: Ettl H., Gerloff J., Heynig H. & Mollenhauer D. (eds) Süßwasserflora von Mitteleuropa, vol. 2 (3). Spektrum, Heidelbergand Berlin.

Kützing F.T. 1833a. Synopsis diatomearum oder Versuch einer systematischen Zusammenstellung der Diatomeen. Linnaea 8: 529–620, pls XIII–XIX [79 figs].

Kützing F.T. 1833b. Algarum Aquae Dulcis Germanicarum. Decas III. Collegit Fridericus Traugott Kutzing, Societ. Bot. Ratisbon. Sodalis. C.A. Schwetschkii et Fil., Halis Saxonum [Halle (Saale)].

Lange-Bertalot H. 1980. Zur systematischen Bewertung der bandförmigen Kolonien bei Navicula und Fragilaria. Kriterien für die Vereinigung von Synedra (subgen. Synedra) Ehrenberg mit Fragilaria Lyngbye. Nova Hedwigia 33: 723–787.

Lyngbye H.C. 1819. Tentamen hydrophytologiae danicae continens omnia hydrophyta cryptogama Daniae, Holsatiae, Faeroae, Islandiae, Groenlandiae hucusque cognita, systematice disposita, descripta et iconibus illustrata, adjectis simul speciebus norvegicis. Schultz, Hafniae [Copenhagen].

Medlin L. & Kaczmarska I. 2004. Evolution of the diatoms: V. Morphological and cytological support for the major clades and a taxonomic revision. Phycologia 43 (3): 245–270.

Morales E.A. 2003. Fragilaria pennsylvanica, a new diatom (Bacillariophyceae) species from North America, with comments on the taxonomy of the genus Synedra Ehrenberg. Proceedings of the Academy of Natural Sciences of Philadelphia 153: 155–166.[0155:FPANDB]2.0.CO;2

Nunes M.L., Silva E.F. & Almeida S.F.P. 2003. Assessment of water quality in the Caima and Mau River basins (Portugal) using geochemical and biological Indices. Water Air and Soil Pollution 149: 227–250.

Ognjanova-Rumenova N., Temniskova-Topalova D. & Valeva M. 1994. Ultrastructure of Fragilaria Lyngbye species (Bacillariophyta) from Neogene sediments in Bulgaria. In: Kociolek J.P. (ed.) Proceedings of the 11th International Diatom Symposium: San Francisco, California, August 12–17, 1990: 291–300. Memoirs of the California Academy of Sciences 17. California Academy of Sciences, San Francisco.

Poulin M., Bérard-Therriault L. & Cardinal A. 1986. Fragilaria and Synedra (Bacillariophyceae): a morphological and ultrastructural approach. Diatom Research 1 (1): 99–112.

Rohlf F.J. & Slice D.E. 1990. Extensions of the Procrustes method for the optimal superimposition of landmarks. Systematic Zoology 39: 40–59.

Round F.E. 1984. The circumscription of Synedra and Fragilaria and their subgroupings. In: Mann D.G. (ed.) Proceedings of the Seventh International Diatom Symposium, Philadelphia, August 22–27, 1982: 241–253. Otto Koeltz Science Publishers, Koenigstein.

Round F.E., Crawford R.M. & Mann D.G. 1990. The diatoms. Biology and morphology of the genera. Cambridge University Press, Cambridge.

Silva P.C. 1962. Classification of algae. In: Lewin R.A. (ed.) Physiology and biochemistry of algae: 827–837. Academic Press, New York & London.

The European Parliament and European Council 2000. Directive 2000/60/EC of the European

Parliament and of the Council establishing a framework for Community action in the field of water policy. Official Journal of the European Union, L. ser. 327: 1–73.

Tuji A. & Williams D.M. 2013. Examination of types in the Fragilaria vaucheriae-intermedia species complex. Bulletin of the National Museum of Natural Sciences Series B 39 (1): 1–9.

Van Heurck H. 1881. Synopsis des Diatomées de Belgique, Atlas. pls XXXI-LXXVII. Ducaju et Cie, Anvers.

Wetzel C.E. & Ector L. 2015. Taxonomy and ecology of Fragilaria microvaucheriae sp. nov. and comparison with the type materials of F. uliginosa and F. vaucheriae. Cryptogamie, Algologie 36 (3): 271–289.

Williams D.M. & Round F.E. 1986. Revision of the genus Synedra Ehrenb. Diatom research 1 (2): 313–339.

Williams D.M. & Round F.E. 1987. Revision of the genus Fragilaria. Diatom research 2 (2): 267–288.

Williams D.M. 2006. Some notes on the classification of Fragilaria, Synedra and their sub-groups. Nova Hedwigia Beiheft 130: 17–34.


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