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Issue: Vol. 731 No. 3: 2 Dec. 2025
Type: Article
Published: 2025-12-02
DOI: 10.11646/phytotaxa.731.3.8
Page range: 294-300
Abstract views: 75
PDF downloaded: 4

Navicula subphyllepta sp. nov. (Naviculaceae, Bacillariophyceae), a new brackish diatom species from France

Université Clermont Auvergne, CNRS, GEOLAB UMR 6042 4 rue Ledru, Clermont-Ferrand, 63057, France
Université Clermont Auvergne, CNRS, GEOLAB UMR 6042 4 rue Ledru, Clermont-Ferrand, 63057, France; LTSER “Zone Atelier Loire”, F-37000 Tours, France
Université Clermont Auvergne, CNRS, GEOLAB UMR 6042 4 rue Ledru, Clermont-Ferrand, 63057, France
Université Clermont Auvergne, CNRS, GEOLAB UMR 6042 4 rue Ledru, Clermont-Ferrand, 63057, France
Meise Botanic Garden Meise, Research Department, Nieuwelaan 38, 1860 Meise, Belgium; University of Antwerp, Department of Biology – ECOSPHERE, Universiteitsplein 1, B-2610 Wilrijk, Belgium
brackish diatoms Marais Poitevin morphology new species Navicula planktonic Algae

Abstract

A new brackish-water diatom species, Navicula subphyllepta Contamine, Beauger & Van de Vijver sp. nov., is described from a managed canal in the Marais Poitevin (Vendée, western France). This taxon was initially misidentified as Navicula phyllepta Kützing, but detailed morphological analysis using light and scanning electron microscopy revealed significant differences in valve dimensions, stria density, and ultrastructural features of the central area and raphe system. The new species was dominant in a pelagic sample from a moderately alkaline site characterized by high conductivity and elevated sulfate and bromide concentrations, reflecting a strong brackish influence. Navicula subphyllepta is compared to similar species, including 1205527114 N. phyllepta, N. phylleptosoma, N. salinarum, and N. lindae, from which it is clearly separated by a combination of morphometric and structural features. The new species is observed seasonally in both planktonic and benthic assemblages. Its description contributes to the growing recognition of taxonomic diversity in brackish diatom floras, which remain understudied in Western Europe.

References

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How to Cite

Contamine, L., Beauger, A., Voldoire, O., Ragot, A. & Vijver, B.V.D. (2025) Navicula subphyllepta sp. nov. (Naviculaceae, Bacillariophyceae), a new brackish diatom species from France. Phytotaxa 731 (3): 294–300. https://doi.org/10.11646/phytotaxa.731.3.8