Sellaphora smirnovii Chudaev et Gololobova, 2015

Chudaev, Dmitry A. & Gololobova, Maria A., 2015, Sellaphora smirnovii (Bacillariophyta, Sellaphoraceae), a new small-celled species from Lake Glubokoe, European Russia, together with transfer of Navicula pseudoventralis to the genus Sellaphora, Phytotaxa 226 (3), pp. 253-260 : 254

Sellaphora smirnovii Chudaev et Gololobova , sp. nov. ( Figs 1–16 )

Valves elliptic-lanceolate with widely protracted, subrostrate and bluntly rounded apices, length 6.4–13.5 μm, width 3.6–4.5 μm. The axial area is narrow, linear, and widens slightly toward central area. Longitudinal furrows border the axial area on external valve surface. The central area is transapically widened, elliptical to rectangular or bow-tie-shaped, bordered by shortened striae of varying length. Striae are not discernible in LM, uniseriate, radiate, becoming parallel towards the ends, 34–37 in 10 μm. Areolae small, circular, occasionally more or less square-shaped, 70–79 in 10 μm. Raphe filiform, external proximal endings are unilaterally deflected pores, external distal endings are long fissures deflected to the same side, opposite the central pores. Valve interior was not studied because we were not able to find valves in suitable position.

Type:— RUSSIA. Moscow Region: Lake Glubokoe, 55° 45’ 18.6” N, 36° 30’ 04.4” E, surface sediments from 5 m water depth, D. A. Chudaev, 31 July 2007 (holotype: MW!, circled specimen in slide 18s1, depicted in Fig. 7 , Diatom collection of the Department of Mycology and Algology. Isotype: LE! slide Chudaev 18s2, Komarov Botanical Institute, St. Petersburg, Russia).

Etymology:— The species is dedicated to Prof. Nikolai Nikolaevich Smirnov, who has intensively studied different aspects of the biota of Lake Glubokoe for many years.

Distribution and ecology:— The taxon is so far known only from Lake Glubokoe. It was found in samples of epiphyton of Elodea canadensis Michx. and Sagittaria sagittifolia L., surface sediments, and from a core of bottom sediments up to 150 cm from bottom surface.

Figures

FIGURES 1–16. Sellaphora smirnovii sp. nov. 1–13. Light microscopy, Fig. 7 illustrates the holotype specimen. 14–16. SEM, external valve view. Scale bars: 10 μm (Figs 1–13), 1 μm (Figs 14–16).