Contributor: Marina Potapova - January 2012
Length Range: 4-11 µm
Width Range: 2.9–4.2 µm
Striae in 10 µm: 12–15
Valves are elliptic. Raphe valve has a narrow linear axial area and a small central area. Raphe is filiform, straight, with slightly expanded distal and proximal ends. Rapheless valve has a linear–lanceolate axial area. Striae are multiseriate, radiate. There are four rows of areolae per stria on the raphe valve, and three rows per stria on the rapheless valve.
Basionym: Platessa bahlsii
Author: Potapova 2012
Length Range: 3.6-11.0 µm
Width Range: 2.9-4.2 µm
Striae in 10 µm: 12-15
Potapova, M. (2012). New species and combinations in monoraphid diatoms (Family Achnanthidiaceae) from North America. Diatom Research 27(1): 29-42. doi:10.1080/0269249X.2011.644636
Platessa bahlsii appears to be a common species in nutrient-rich streams of the eastern US.