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Issue: Vol. 726 No. 2: 30 Oct. 2025
Type: Article
Published: 2025-10-30
DOI: 10.11646/phytotaxa.726.2.1
Page range: 61-73
Abstract views: 297
PDF downloaded: 10

A revision of the Fragilaria pectinalis-complex in Europe (Bacillariophyceae, Fragilariaceae) with the description of a new species

Meise Botanic Garden, Research Department, Nieuwelaan 38, 1860 Meise, Belgium, University of Antwerp, Department of Biology – ECOSPHERE, Universiteitsplein 1, 2610 Wilrijk, Belgium
Botanischer Garten und Botanisches Museum, Freie Universität Berlin, Königin-Luise-Str. 6-8, 14195 Berlin, Germany
Luxembourg Institute of Science and Technology (LIST), Environmental Research & Innovation (ERIN) Department, Observatory for Climate, Environment and Biodiversity (OCEB), 41 rue du Brill, 4422 Belvaux, Luxembourg
The Natural History Museum, Department of Life Sciences, Cromwell Road, London, SW7 5BD, UK
Europe Fragilaria pectinalis historic material morphology new species Algae

Abstract

During routine biomonitoring in Europe, an unknown Fragilaria taxon was frequently observed in western Europe, that was initially identified as Fragilaria pectinalis, a species described in the late eighteenth century from the UK and often misidentified. The epitype material of Conferva pectinalis collected in 1802 by Dillwyn was analysed using both light and scanning electron microscope observations. Additional historic material from the Rabenhorst and Grunow collections was likewise investigated and compared to the unknown French Fragilaria populations identified in Wetzel & Ector (2015) as F. pectinalis. While the Rabenhorst material was identified as F. pectinalis, the taxon described by Grunow as Synedra capitellata f. striis-distantioribus was transferred to the genus Fragilaria and raised to species level. The French populations showed sufficient morphological differences to be separated as a new species, Fragilaria lucectorii, based on valve outline, shape of the apices and stria density. Comparisons are made with similar taxa and brief notes on their ecology are added.

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How to Cite

van De Vijver, B., Kusber, W.-H., Wetzel, C.E. & Williams, D.M. (2025) A revision of the Fragilaria pectinalis-complex in Europe (Bacillariophyceae, Fragilariaceae) with the description of a new species. Phytotaxa 726 (2): 61–73. https://doi.org/10.11646/phytotaxa.726.2.1