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Diatoms of the United States is now known as Diatoms of North America.
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Planothidium dubium

(Grunow) Round and Bukht. 1996      Category: Monoraphid
BASIONYM: Achnanthes lanceolata var. dubia

Planothidium delicatulum


Planothidium frequentissimum

SEM scalebar = 5 ┬Ám

Site ID: ANSP MO000295

Site Name: Willow Creek, MT

Latitude: 47.825

Longitude: -116.646

Caption: Internal view of rapheless valve

Contributor: - August 2011