Platessa bahlsii Potapova 2012

Lee, Sang Deuk, Yun, Suk Min, Cho, Pyo Yun, Yang, Hye-Won & Kim, Oe Jung, 2019, Newly Recorded Species of Diatoms in the Source of Han and Nakdong Rivers, South Korea, Phytotaxa 403 (3), pp. 143-170 : 164

Platessa bahlsii Potapova 2012 *

Figure 110

Original description: Potapova (2012), p. 38, figs 84–96.

Key literature: Potapova (2012), p. 38, figs 84–96.

Specimen examined: Tables 1, 2.

Dimension: Length 5.8 μm, width 3.2 μm; 1–2 striae in 1 μm on the raphe valve.

Description: The valves are elliptical and broad toward valve center. The raphe valve has narrow linear axial area and small central area. The raphe is slightly filiform, straight, with slightly expanded distal. The external proximal raphe endings are straight. The striae are multiseriate and radiate. Three to four rows of areolae per stria on the raphe valve.

Remarks: Platessa bahlsii differs from P. conspicua by small central area on the raphe valve, smaller cell size, and having three to four rows of areolae in striae. The striae are evenly distributed on the valve face. P. conspicua has rectangular central area and biseriate striae. P. bahlsii can be easily confused with some small species of Planothidium ( Potapova 2012) .

Distribution and ecology: Platessa bahlsii appears to be widely distributed in North America, but it is difficult to estimate its range as it was most likely confused with P. conspicua in the past ( Potapova 2012).