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Diatoms of the United States is now known as Diatoms of North America.
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Psammothidium harveyi

(Reimer) Potapova 2012      Category: Monoraphid
BASIONYM: Achnnathes harveyi Reimer 1966

Psammothidium didymum


Psammothidium helveticum

LM scalebar = 10 µm = 80 pixels.


Contributor: Marina Potapova - January 2012
Length Range: 10-29 µm
Width Range: 7.0-9.5 µm
Striae in 10 µm: 22-25


Valves are elliptic-lanceolate with rostrate apices. The raphe valve has a narrow linear axial area widening at the valve center into a transversely rectangular asymmetric central area that often reaches the valve margins. The raphe is straight, but its short terminal fissures are gently curved to opposite sides. The proximal external raphe ends are expanded and sharply turned to the same side in SEM, but appear straight in LM. The axial area on the rapheless valve is linear and widens into an asymmetric central area. The striae are uniseriate. The external areolae openings are mostly isodiametric, but transapically elongated near valve margins. Internally, areolae are transapically elongated. There are 23–28 areolae in 10 μm along each stria on the rapheless valve and 28–35 on the raphe valve. The girdle bands are plain and open.

Original Description

Basionym: Achnnathes harveyi
Author: Reimer 1966
Length Range: µm
Striae in 10 µm:

Original Description

Original Images

Cite This Page:
Potapova, M. (2012). Psammothidium harveyi. In Diatoms of the United States. Retrieved May 24, 2018, from

Species: Psammothidium harveyi

Contributor: Marina Potapova

Reviewer: Sarah Spaulding


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

Reimer, C.W. (1966). Consideration of fifteen diatom taxa (Bacillariophyta) from the Savannah River, including seven described as new. Notulae Naturae (Academy of Natural Sciences of Philadelphia) 397:1-15.

Links & ID's

Index Nominum Algarum (INA)

California Academy of Sciences (CAS)

North American Diatom Ecological Database (NADED)


Autecology Discussion