Nitzschia elegantula Grunow, 1885

Schuster Meise Botanic Garden, Tanja M., 2025, Observations and typification of two diatoms described by Grunow from Blankenberghe, Belgium: Nitzschia elegantula Grunow and Craticula halophila (Grunow) D. G. Mann (Bacillariophyceae), Notulae Algarum 368, pp. 1-7 : 3

Nitzschia elegantula Grunow ( Figs 9–34)

≡ Nitzschia microcephala var. elegantula (Grunow) Van Heurck 1885: 183

Lectotype (here designated): BR-4866 ( BR!, Meise Botanic Garden). Fig. 15 illustrates the lectotype specimen.

Registration (of lectotypification): http://phycobank.org/105448

Type locality: Blankenberghe , Belgium, Van Heurck Types du Synopsis n°12, sample and slides kept at BR .

Description: Valves lanceolate (Figs 10,11) to linear-lanceolate with convex margins, usually with a central, often asymmetrical constriction. Apices protracted, rostrate to weakly capitate. Valve dimensions (n=25): length 12–24 µm, width 3–3.5 µm. Keel round, slightly elevated from the valve face and mantle. Raphe filiform, eccentrically placed on one side to the valve, continuously running from one apex to another. Terminal raphe fissures hooked. Internally, terminal raphe ends on small helictoglossa. Fibulae equidistant throughout, small, square to rectangular, connected to 2–3 striae, 11–14 in 10 µm. Striae coarse, uniseriate, composed of irregularly transapically elongated areolae, 23–28 in 10 µm. Internally, areolae are occluded with a fine poroid hymen plate.