Gomphoneis hastatoides Kociolek & Kulikovskiy, 2013

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 : 8

Gomphoneis hastatoides Kociolek & Kulikovskiy , sp. nov. ( Figs 40–60 )

Valves distinctly clavate with broadest portion of the valve located past the central nodule towards the footpole, with headpole broadly rounded and footpole rounded. Length 30–65 µm, breadth 12–17 µm. Axial area straight, expanded to form a distinctly orbicular central area. Raphe lateral, straight, with external proximal raphe ends dilated. Internal distal raphe ends distinct. External distal raphe ends nearly straight, extending onto the valve mantle. Central area with 4 (rarely 5) isolated stigmoids. At the footpole the raphe bisects the distinct apical pore fields that resemble the striae. Striae costate, individual areolae cannot be resolved with LM. Striae radiate about the center of the valve and towards the footpole, becoming parallel near the headpole. Striae 12–14/ 10 µm. Septa and pseudosepta present at both poles.

Type:— RUSSIA: Bolshoi Ushkaniy Island (rock), Lake Baikal, 16.07.2011, leg. M. Kulikovskiy ( IBIW, slide no. 18575m!, holotype here designated (= Fig. 41 ); COLO slide 18575p, isotype) .

Observations:— This species is distinguished from G. hastata by the shape of the valves, with G. hastatoides being broadest towards the footpole.

Figures

PLATE 3: LM. Figs 40–60: Gomphoneis hastatoides sp. nov. Fig. 41 is of the holotype.Scale bar = 10 µm for all figures.