Gomphoneis reichardtii Kociolek, Kulikovskiy & Solak, 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 : 15

Gomphoneis reichardtii Kociolek, Kulikovskiy & Solak , sp. nov. ( Figs 223–228 , 422–424 )

Valves lanceolate-clavate with headpole rounded and footpole narrowly rounded. Length 13.0– 21.5 µm, breadth 4–5 µm. Axial area very narrow, expanded laterally at the center to form a rectangular central area, bordered by 1–2 shortened striae more coarsely arranged than other striae on both sides of the central area at the margins. 4 isolated stigmoids are positioned around the central area. Raphe weakly lateral, slightly undulate. External proximal raphe ends dilated slightly. External distal raphe ends extend onto mantle at both poles. Costate striae radiate around the center and at footpole, radiate towards headpole and parallel at apex. Striae number 13–15/ 10 µm. Footpole with small apical pore field. Septa and pseudosepta present at poles.

The small valves of this species have the apical pore field restricted to the valve mantle, while the proximal raphe ends are dilated ( Fig. 422 ). Stigmoidal openings can be of different sizes ( Fig. 422 ). The distal raphe ends are deflected weakly onto the mantle at both poles. Internally, the central nodule is raised slightly internally, and bears the small, recurved proximal raphe ends. The internal stigmoidal opening are round and unoccluded ( Figs. 423, 424 ). Pseudosepta are present at the poles.

Type:— RUSSIA: Lake Baikal , bay near Enkhaluk village, on macrophyte, N52 o 27.042, E106 o 53.215, 14.07.2011, leg. M. Kulikovskiy ( IBIW slide no. 18599m, holotype designated here (= Fig. 223 ); COLO slide no. 18599p, SZCZ slide no. 18599a, isotypes) .

Etymology:— Named in honor of Mr. Erwin Reichardt, Treuchtlingen, Germany, for his contributions to the study of gomphonemoid diatoms.

Figures

PLATE 7: LM. Figs 169–174: Gomphoneis metzeltinii sp. nov. Fig. 169 is of the holotype. Figs 175–192: G. cf. subcapitata. Figs 193– 200: G. subcapitata sp. nov. Fig. 200 is of the holotype. Figs 201–214: G. inconspicua sp. nov. Fig. 201 is of the holotype. Figs 215– 222: G sp. cf. subcapitata. Figs 223–228: G. reichardtii sp. nov. Fig. 223 is of the holotype. Figs 229–237: G. sp. cf. skabitchevskii. Figs 238–250: G.sp. cf. skabitchevskii. Figs 251–260: G. skabitchevskii sp. nov. Fig. 258 is of the holotype. Figs 261–282: G.sp. cf. reichardtii. Scale bar = 10 µm for all figures.

PLATE 18: SEM. Gomphoneis reichardtii. Figs 422–424: Fig. 422: External valve view with stigmoids evident. The raphe is straight and the proximal ends are dilated. The apical pore field is positioned only on the valve mantle. Figs 423–424: Internal valve views with pseudosepta and helictoglossae evident at the poles. Stigmoids occur around the internally raised central nodule.