Gomphoneis qii Q. You & Kociolek, 2013

You, Qingmin, Kociolek, John Patrick & Wang, Quanxi, 2013, New Gomphoneis Cleve (Bacillariophyceae: Gomphonemataceae) species from Xinjiang Province, China, Phytotaxa 103 (1), pp. 1-24 : 6-8

Gomphoneis qii Q. You & Kociolek , sp. nov. ( Figs 26–38 ; figure 27 is holotype)

Type:— CHINA. Bulunkou Township , Kunlun Mountains ( SHTU, slide XJ-071013! holotype illustrated in figure 27) .

In LM, valves lanceolate-clavate with headpole slightly protracted and broadly rounded, footpole tapered and narrowly rounded. Length 39.0–42.0 µm, breadth 6.5–7.0 µm. Axial area narrow, straight, expanded laterally at the center to form a broad, rectangular central area. Stigmoids in the central area wanting. Raphe barely lateral, weakly undulate, with external proximal ends dilated slightly, and extending near the central area, and external distal raphe ends straight, extended to the valve terminus at both poles. Internal proximal raphe ends small, tightly recurved in the same direction, while internal distal raphe ends (“terminal nodules”) are positioned well before the valve terminus. Costate striae number 10–12/ 10 µm, are arched or straight about the center of the valve and radiate, becoming straight and radiate to parallel towards the poles. Septa and pseudosepta evident at the poles. Apical pore fields indistinct.

On the valve exterior, SEM observations show striae composed on small, round puncta with two rows of alternating puncta ( Figs 31–34 ). While striae terminate in a single punctum at the axial area ( Figs 33, 34 ), only at the central area do they taper and have more than one row of puncta ( Fig. 33 ). The raphe has dilated proximal ends at the center, and the distal ends extend straight onto the valve at both ends ( Figs 31, 33 ). The apical pore fields are composed of round porelli, similar in shape to the puncta. The apical pore fields are present on the valve face and extend onto the mantle ( Fig. 34 ).

Internally, the raphe is located on the raised sternum ( Fig. 35 ), while the proximal ends are recurved opposite on another at the border of the central nodule ( Figs 35, 37 ). Helictoglossae and pseudosepta are prominent at the ends ( Figs 36, 38 ). The helictoglossae are positioned on line with the raphe slit ( Fig. 38 ).

Etymology:— Named for Prof. Yuzao Qi, Jinan University, China, for his pioneering work on the diatoms of Chin, and for his continued support of diatom research, and to celebrate the occasion of his 80 th birthday.

Distribution and ecology:— Bulunkou Township, Kunlun Mountains, Xinjiang, China, altitude 3200m, pH 9.6, collected from an unnamed puddle, epiphytic on aquatic vascular plants (summarized in Table 1).

Figures

PLATE 5, FIGURES 26–30. Gomphoneis qii, LM. Valve views showing size diminution series. Figure 27 is the holotype. Scale bar = 10 µm for all figures.

PLATE 6, FIGURES 31–34. G.qii. SEM, external views. Fig. 31. Entire valve view showing shape of the valve and dilated proximal raphe ends. Fig. 32. Headpole, with distal raphe end extended from valve face to mantle. Striae are doubly-punctae, with areolae small and round. Fig. 33. Central area showing striae of reduced length and external proximal raphe ends. Fig. 34. Footpole, with porelli of the apical pore fields similar in position and shape to the areolae.

PLATE 7, FIGURES 35–38. G.qii. SEM, internal views. Fig. 35. Entire valve view showing prominent axial area and central nodule, the large helictoglossae and pseudosepta. The rectangular shape of the central area is evident. Fig. 36. Headpole, showing the pseudoseptum. Fig. 37. Central area with the internally elevated central nodule bearing the recurved proximal raphe ends. Fig. 38. Footpole, with helictoglossa and pseudosepteum obvious.