Humidophila vidalii (Van de Vijver, Ledeganck & Beyens) R.L.Lowe et al., 2014

Chattová, Barbora, Lebouvier, Marc & Vijver, Bart Van De, 2018, Morphological and taxonomical analysis of the terrestrial diatom genus Humidophila (Bacillariophyta) on Ile Amsterdam and Ile Saint-Paul (Southern Indian Ocean), Phytotaxa 336 (1), pp. 28-42 : 34

Humidophila vidalii (Van de Vijver, Ledeganck & Beyens) R.L.Lowe et al. ( Figs 80–100 )

Morphological observations:—Valves linear with broadly rounded, never protracted apices. Larger valves with clear concave margins. Valve dimensions (n=30): length 7.0 – 17.5 μm, width 2 – 3.5 μm. Axial area linear, broad, slightly narrowing towards the poles. Central area absent. Raphe straight, filiform with clearly depressed distal and proximal raphe pores. Occasionally, T-shaped endings present. Striae composed of very short, almost rounded areolae, located close to the valve margins, 33 – 36 in 10 μm. Areolae on the mantle equidistant, more closely together towards the poles.

Ecology and associated diatom flora:—This species was mostly found in wet to quasi-dry terrestrial bryophytes (FIV-VI) especially in the areas of Grand Tunnel, Jardin Météo and Del Cano. The samples are dominated by Humidophila crozetikerguelensis , H. amsterdamensis , Eunotia paludosa , Sellaphora barae Van de Vijver & E.J.Cox (2013: 40) , Orthoseira verleyenii Van de Vijver (in Lowe et al. 2013: 41), Mayamaea cavernicola Van de Vijver & E.J.Cox (2013: 40) , an at present unidentified Nitzschia Hassall (1845: 435) species and Ferocia setosa (Greville) Van de Vijver & Houk (Van de Vijver et al. 2017).

Figures

FIGURES. 80–100. Humidophila vidalii (Van de Vijver, Ledeganck & Beyens) R.L.Lowe et al. Light (LM) and scanning electron micrographs (SEM). 80–96. LM of valve views. 97–99. SEM of an entire valve (externally). 100. SEM of internal valve view. Note the missing central area. LM scale bar = 10 μm. SEM scale bars = 1 μm.