Gomphoneis

Kociolek, John P., Kulikovskiy, Maxim S. & Solak, Cüneyt N., 2013, The diatom genus Gomphoneis Cleve (Bacillariophyceae) from Lake Baikal, Russia, Phytotaxa 154 (1), pp. 1-37 : 13

Gomphoneis cf. witkowski (Figs 144–152)

Valves lanceolate-clavate apices rounded. Length 29–45 µm, breadth 7–9 µm. Axial area narrow, expanded at the center to form a rounded to irregular rectangular-shaped central area bordered by 2–5 shortened striae more coarsely separated from other striae. Central area contains 4 isolated stigmoids positioned around the central area. Central area not expanded to the margin. Raphe lateral, straight, with external proximal raphe ends distinctly dilated. External distal raphe ends extend nearly straight onto the valve mantle. Striae costate, radiate about the center of the valve, to the footpole and towards the headpole, before becoming parallel at the apex. Striae 12–14/ 10 µm. Apical pore field distinct, composed of defined rows of porelli. Septa and pseudosepta distinct, especially at the footpole.

Observations: —This represents the morphologies of specimens identified by Kociolek & Stoermer (1988b, their figures 31–34) as G. quadripunctata (Østrup) Dawson ex Ross & Sims from Lake Baikal. Our review of micrographs published of the type specimens of G. quadripunctata ( Kociolek & Stoermer 1988b; Tuji 2005) from Lake “Kossogol” ( Mongolia) suggests we cannot confirm the presence of this taxon in Lake Baikal.