Adlafia babeiensis Glushch., Kulik. & Kociolek, 2020

Glushchenko, Anton M., Kociolek, John Patrick, Kuznetsova, Irina V. & Kulikovskiy, Maxim S., 2020, Four new species from the diatom (Bacillariophyceae) genus Adlafia Moser, Lange-Bertalot & Metzeltin from waterbodies of Vietnam, PhytoKeys 162, pp. 13-27 : 13

Adlafia babeiensis Glushch., Kulik. & Kociolek sp. nov. Figs 3 , 4

Holotype.

Slide no. 02168 in collection of Maxim Kulikovskiy at the Herbarium of the Institute of Plant Physiology Russian Academy of Science, Moscow, Russia, represented here by Fig. 3A .

Type locality.

Vietnam. Bắc Kạn Province, Ba Bể Lake, benthos, 22°23.605'N, 105°36.856'E, 163 m elev., leg. E.S. Gusev, 29.04.2015.

Description.

LM (Fig. 3A-L ). Valves lanceolate with rostrate ends. Length 11.5-14.0 μm (12.8 ± 0.6; n = 21), breadth 4.0-4.5 μm (4.3 ± 0.1; n = 21). Axial area narrow, almost linear. Central area weakly expressed or absent. Raphe filiform. Striae indistinct in LM, weakly radial at the central area, convergent towards to the ends. Areolae not resolved in LM.

SEM, external view (Fig. 4A-C ). Valve face flat. Axial area linear. Central area absent. Raphe filiform, weakly lateral. Proximal raphe endings slightly expanded, deflected. Distal raphe endings positioned on the valve mantle, hooked and curved in the same direction, and terminating at the junction valve face-mantle. Striae uniseriate, radiate, becoming abruptly convergent approaching apices, Striae 36-40 in 10 μm (38 ± 0.1; n = 21). Areolae rounded or rectangular, occluded by hymenes. Slit-like opening of apical areolas invisible. Areolae 65-70 in 10 μm (67.5 ± 0.8; n = 21).

SEM, internal view (Fig. 4D ). The raphe straight, lying in a prominent and raised raphe-sternum. Proximal raphe endings deflected towards primary side of valve. Distal raphe endings terminating in small helictoglossae. Striae continuing on to valve mantle. Short striae alternate with longer striae at the center of the valve. Areolae rounded. Openings of apical areolae apically elongated.

Etymology.

Epithet refers to the lake of Vietnam where the new species was found.

Distribution.

Vietnam. Known only from the type locality.

Figures

Figure 3. A-L Adlafia babeiensis Glushch., Kulik. & Kociolek, sp. nov. LM, DIC, size diminution series. Slide no 02168. Holotype (A). Scale bar: 10 μm.

Figure 4. A-D Adlafia babeiensis Glushch., Kulik. & Kociolek, sp. nov. A-C SEM, external views D internal views. Sample no 02168. Scale bars: 2 μm (A, C), 1 μm (B, D).