Two new marine species of Cocconeis (Bacillariophyceae) from the west coast of Sweden

  • Adil Y. Al-Handal Department of Biological and Environmental Sciences, University of Gothenburg, Göteborg, Sweden.
  • Catherine Riaux-Gobin LABEX “CORAIL”, PSL USR 3278 CNRS-EPHE, CRIOBE-Université de Perpignan, FR-66860, France.
  • Regine Jahn Botanischer Garten und Botanisches Museum Berlin-Dahlem, Freie Universität Berlin, Germany.
  • Angela Katarina Wulff Department of Biological and Environmental Sciences, University of Gothenburg, Göteborg, Sweden.
  • Alison Minerovic The Academy of Natural Sciences of Drexel University, Philadelphia, PA 19103, USA.
Keywords: Cocconeis, diatoms, epiphytes, marine, new species, Sweden


This paper is part of a project of studying benthic diatom biodiversity on marine coastal regions of Sweden with focus on rare and less known species. Two new species of Cocconeis Ehrenb. are described from Vrångö, a small island in the west coast of Sweden. Both species were found as epiphytic on the green alga Ulva intestinalis L. Cocconeis magnoareolata Al-Handal, Riaux-Gob., R.Jahn & A.K.Wulff sp. nov. is a small species not exceeding 9 µm in length and characterized by having large subquadrangular areolae on the sternum valve. Cocconeis vrangoensis Al-Handal & Riaux-Gob. sp. nov. appears similar to some taxa of the ‘Cocconeis scutellum complex’, but differs by its stria density on both valves and variable features of the areola and valvocopula ultrastructure. Detailed descriptions based on light and electron microscopy examination, a comparison with closely related taxa, as well as a description of the habitat of both species are here presented.


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How to Cite
Al-Handal, A. Y., Riaux-Gobin, C., Jahn, R., Wulff, A. K., & Minerovic, A. (2019). Two new marine species of Cocconeis (Bacillariophyceae) from the west coast of Sweden. European Journal of Taxonomy, (497).