Hantzschia sinensis, You & Kociolek, 2015

You, Qingmin, Kociolek, John Patrick & Wang, Quanxi, 2015, The diatom genus Hantzschia (Bacillariophyta) in Xinjiang Province, China, Phytotaxa 197 (1), pp. 1-14 : 4-5

Hantzschia sinensis Q-M You & J. P. Kociolek, sp. nov. (Figs 14–25; figure 16 = holotype)

Valves not obviously asymmetrical to the apical axis. Ventral and dorsal margins all straight throughout but with slight depression in the middle of both margins. Ends obliquely cuneate and apices slightly protracted, commonly narrow-rostrate, not bent towards either margin. Length 50–90 μm, breadth 8–10 μm. Fibulae 8–9 in 10 μm, but not equidistant, median two slightly more distant than the others, each of them connected with 1 (rarely 2–4) transapical costa(e). External raphe branches straight and continuous in the middle of the valve (Fig. 22), while internal raphe branches not continuous and slightly deflected to dorsal margin (Fig. 23). Striae parallel throughout, 16–18 in 10 μm. Striae puncta not discernible in LM. In SEM, puncta appear as small, rounded poroids (Figs 22–25), c. 30–36 in 10 μm. Helictoglossae prominent and aligned with raphe at both ends of the valve interior (Fig. 25).

Type:— CHINA. Shache ( SHTU, slide XJ-071054! Holotype = figure 16).

Etymology:— The specific epithet is named for China.

Distribution and ecology:— Hantzschia sinensis was found in the same habitats as H. pseudobardii in samples 010116, 010181 and 071054.

Observations::— H. sinensis is most similar to H. acuticapitata ( Zidarova et al. 2010: 324) in outline and dimensions, although H. sinensis is slightly longer and wider than H. acuticapitata . The two species have some differences in valve structure, for example H. sinensis has a lower striae density and fewer number of puncta per 10 μm (see Table 2).