PLATE 6. Eunotia obtusisaculea Q. Liu, S. L in New and Interesting Diatoms from the Shiwan Wetwalls, Yunnan Province, China. III. Valve ultrastructure of four new species of Eunotia (Bacillariophyceae: Eunotiales)

PLATE 6. Eunotia obtusisaculea Q. Liu, S. L. Xie & Kociolek, sp. nov. Figures 43–50. Scanning electron microscope images. Figures 43–46, external views. Fig. 43. Whole valve view, showing thickened interstriae and blunt spines about the dorsal margin. Fig. 44. View of valve mantle near apex of the valve. Raphe is sinuous, dilated at the proximal end and barely extending onto the valve face. Fig. 45. View of mid-valve showing solid blunt spines on the dorsal margin. Thick interstriae separate striae which bear round occlusions. Fig. 46. Girdle view of a frustule near apex. Raphe branches can be seen on both valves. One valve possesses 10 cingulum elements, which all bear poroids. Figs. 47–50, internal views. Fig. 47. Whole valve. Striae occur in narrow troughs. Pseudosepta are present at the poles. Fig. 48. Valve apex, with helictoglossa and rimoportula present. Fig. 49. Mid-valve showing narrow troughs of the striae. Fig. 50. Apex of the valve.