Gomphoneis parahastata Kulikovskiy & Kociolek, 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 : 5

Gomphoneis parahastata Kulikovskiy & Kociolek , sp. nov. ( Figs 12–31 , 380–381)

Valves lanceolate-clavate with headpole broadly rounded, footpole rounded. Length 32–78 µm, breadth 12–17 µm. Axial area straight, narrow, expanded by irregularly long and short striae about the center to form an irregular somewhat circular central area with 4 stigmoids that appear to be offset from one another. Raphe is lateral with external proximal raphe ends dilated and distal ends nearly straight and extending onto the mantle at both apices. Striae composed of two rows of areolae, resolvable with LM. Striae radiate, nearly parallel near the headpole. Striae 12–14/ 10 µm. Septa and pseudosepta present at poles. Apical pore field distinct composed of stria-like rows or porelli. In the SEM the valve exterior has dilated proximal raphe ends and isolated stigmoids in depressions in the irregularly rounded central area ( Figs 380, 381). The striae are composed of two rows of areolae ( Figs 380, 381), and the apical pore fields appear as compressed striae ( Fig. 381).

Type:— RUSSIA: Bolshoi Ushkaniy Island , Lake Baikal ( IBIW, slide no. 15651m!, in collection Maxim Kulikovskiy, 20.07.1965, leg. A.P. Skabitschewsky, holotype here designated (= Fig. 15 ); COLO slide no. 15651p; SZCZ slide no. 15651°, isotypes) .

Figures

PLATE 1: LM. Figs 1–11: Gomphoneis hastata. Figs 12–17: G. parahastata sp. nov. Fig. 15 is of the holotype. Scale bar = 10 µm for all figures.

PLATE 2: LM. Figs 18–31: Gomphoneis parahastata sp. nov. Figs 32–39: G.lata. Scale bar = 10 µm for all figures.