Diploneis sp. 3

Jovanovska, Elena, Levkov, Zlatko & Edlund, Mark B., 2015, The genus Diploneis Ehrenberg ex Cleve (Bacillariophyta) from Lake Hövsgöl, Mongolia, Phytotaxa 217 (3), pp. 201-248 : 241

Diploneis sp. 3 ( Fig. 270 )

The valve is elliptical with convex margins and round ends. The valve length is 39.0 μm, and the valve breadth is 20.5 μm. The axial area is linear to lanceolate, expanding toward the round central area. The central area is 4.5 μm wide. The longitudinal canal is lanceolate, expanded in the mid-valve, with two rows of areolae that coalesces into one towards the valve apices. The raphe is straight with expanded proximal ends. The striae are radiate, 11 in 10 μm, composed of round areolae, 15 in 10 μm.

Observations: —With respect to the valve outline, Diploneis sp. 3 can be associated with D. spectabilis and D. mongolica . However, the small number of observed valves does not enable critical comparisons to morphologically allied species. Therefore, additional observations are needed in order to define Diploneis sp. 3 .

Ecology and Distribution: —M068A: found in one epilithic collection at 10 cm depth in southern Lake Hövsgöl.

Figures

FIGURES 253–271. LM and SEM external valve views. Fig. 253. Diploneis cf. eximia, LM valve view. Figs 254, 255. Diploneis cf. minuta, SEM external valve views. Fig. 254. Valve view. Fig. 255. Proximal raphe endings. Figs 256–259. Diploneis sp. 1. Fig. 256. LM valve view. Fig. 257. Central area with proximal raphe endings, SEM. Fig. 258. Distal raphe endings, SEM. Fig. 259. View of the entire valve, SEM. Figs 260–269.Diploneis sp. 2, LM valve views. Fig. 270. Diploneis sp. 3, LM valve view.Fig. 271. Diploneis sp. 3, LM valve view. Scale bars = 10 μm (Figs 253, 256, 260–271); 5 μm (Figs 254, 259); 2 μm (Figs 255, 257, 258).