taxonID	type	description	language	source
03AA8786FFE7DF14FF7D938DFC113658.taxon	description	Description: — Valves elliptic-lanceolate with broadly rounded, convex margins, gradually tapering towards the weakly protracted, acutely rostrate apices (Figs 1 – 17). Smaller specimens with less elongated, more cuneately rounded apices (Figs 18 – 22). Valve dimensions (n = 50): length 15 – 24 µm, width 5.0 – 6.5 µm. Axial area very narrow, externally formed by a slightly raised raphesternum (Fig. 28). Central area small but distinct, asymmetrical. Primary side of central area bordered by 3 abruptly shortened striae whereas secondary side, central area bordered by several gradually shortening striae, forming an elongated convex border (Fig. 28). Occasionally, very short striae inserted near the margin of the central area (e. g. Figs 3, 5, 7). Raphe filiform with weakly curved to straight external raphe branches. Central raphe endings slightly expanded, deflected to the secondary side (Fig. 28). Terminal raphe fissures unilaterally hooked towards secondary side (Fig. 28). Voigt discordance clearly developed, though often only visible in half of the valves (Fig. 28, arrow). Striae uniseriate, composed of lineolae, as long or slightly shorter as the virgae, 17 – 21 in 10 μm. Striae distinctly curved, radiate and more distantly spaced near the central area, becoming parallel to weakly convergent, more densely packed at the apices. Lineolae becoming longer towards the apices and the raphesternum (Fig. 28). Internally, raphe running weakly lateral of the raphe sternum with the raphe slit opening on the side (Fig. 29). Sternum distinctly widened at the central area (Fig. 30). Central raphe endings located in the middle of the central area (Fig. 30), unilaterally deflected. Terminal raphe endings terminating onto small helictoglossae (Fig. 29). Lineolae internally covered by individual hymenes (Fig. 30).	en	Contamine, Léa, Beauger, Aude, Voldoire, Olivier, Ragot, Angèle, Vijver, Bart Van De (2025): Navicula subphyllepta sp. nov. (Naviculaceae, Bacillariophyceae), a new brackish diatom species from France. Phytotaxa 731 (3): 294-300, DOI: 10.11646/phytotaxa.731.3.8, URL: https://doi.org/10.11646/phytotaxa.731.3.8
03AA8786FFE7DF14FF7D938DFC113658.taxon	materials_examined	Type: — Marais Poitevin, sample 23 DIAT _ plank (Vendée department, Pays de la Loire region, France), 46 ° 19 ’ 33.8484 ” N, 1 ° 8 ’ 52.5790 ” W, coll. date 29.04.2025, leg. L. Contamine. (holotype slide BR- 4914 = Fig. 6, isotype slide 460, University of Antwerp, Belgium). PhycoBank registration: http: // phycobank. org / 106064	en	Contamine, Léa, Beauger, Aude, Voldoire, Olivier, Ragot, Angèle, Vijver, Bart Van De (2025): Navicula subphyllepta sp. nov. (Naviculaceae, Bacillariophyceae), a new brackish diatom species from France. Phytotaxa 731 (3): 294-300, DOI: 10.11646/phytotaxa.731.3.8, URL: https://doi.org/10.11646/phytotaxa.731.3.8
03AA8786FFE7DF14FF7D938DFC113658.taxon	etymology	Etymology: — The specific epithet refers to the similarity with Navicula phyllepta and its smaller valve dimensions.	en	Contamine, Léa, Beauger, Aude, Voldoire, Olivier, Ragot, Angèle, Vijver, Bart Van De (2025): Navicula subphyllepta sp. nov. (Naviculaceae, Bacillariophyceae), a new brackish diatom species from France. Phytotaxa 731 (3): 294-300, DOI: 10.11646/phytotaxa.731.3.8, URL: https://doi.org/10.11646/phytotaxa.731.3.8
03AA8786FFE7DF14FF7D938DFC113658.taxon	biology_ecology	Ecology & associated diatom flora: — The type material for N. subphyllepta was observed in a pelagic sample collected from a canal in Marais Poitevin, in the ‘ drained marsh’, near la Baie de l’Aiguillon. The spring canal water was characterized by a moderately alkaline pH (8.5), a very high conductivity (12,000 µS / cm), a medium to high dissolved oxygen level (77 % saturation), very high sulfate concentrations (1,041.49 mg / L), low nitrate levels (0.63 mg / L), elevated phosphate concentrations (0.16 mg / L), and high overall ion concentrations. In particular, bromide levels were very high (13.24 mg / L), indicative of a strong saline and marine influence at the site. The sample was dominated by N. subphyllepta. Subdominant taxa include Conticribra weissflogii (Grunow in Van Heurck 1885: 210) Stachura-Suchoples & D. M. Williams (2009: 482), Navicula paul-schulzii Witkowski & Lange-Bertalot (in Witkowski 1994: 154), Fallacia pygmaea (Kützing 1849: 77) Stickle & D. G. Mann (in Round et al. 1990: 668), Cyclotella atomus (1937: 143), Thalassiosira pseudonana Hasle & Heimdal (1970: 565), Tryblionella apiculata W. Gregory (1857: 79), and several at present unknown taxa from the genera Cyclotella and Navicula. This diatom flora clearly reflects the brackish conditions of the habitat and given the large size of the Navicula subphyllepta population, it is safe to state that it is clearly a brackish Navicula species. N. subphyllepta has also been observed during other seasonal surveys. This species occurred in the planktonic community in October and November at low densities, and in benthic and planktonic community in March, April, (May and June) at higher densities.	en	Contamine, Léa, Beauger, Aude, Voldoire, Olivier, Ragot, Angèle, Vijver, Bart Van De (2025): Navicula subphyllepta sp. nov. (Naviculaceae, Bacillariophyceae), a new brackish diatom species from France. Phytotaxa 731 (3): 294-300, DOI: 10.11646/phytotaxa.731.3.8, URL: https://doi.org/10.11646/phytotaxa.731.3.8
