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Diatoms of the United States is now known as Diatoms of North America.
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Platessa bahlsii

Potapova 2012      Category: Monoraphid

Planothidium rostratum


Platessa conspicua

LM scalebar = 10 µm = 80 pixels.


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.

Original Description

Author: Potapova 2012
Length Range: 3.6-11.0 µm
Width Range: 2.9-4.2 µm
Striae in 10 µm: 12-15

Original Description

Original Images

Cite This Page:
Potapova, M. (2012). Platessa bahlsii. In Diatoms of the United States. Retrieved May 22, 2018, from

Species: Platessa bahlsii

Contributor: Marina Potapova

Reviewer: Loren Bahls


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

Links & ID's

Index Nominum Algarum (INA)

California Academy of Sciences (CAS)

North American Diatom Ecological Database (NADED)


Autecology Discussion

Platessa bahlsii appears to be a common species in nutrient-rich streams of the eastern US.