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Diatoms of the United States is now known as Diatoms of North America.
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Rapheless valve



The proximal internal terminations of the raphe in a rectangular, elevated, elongate structure. This structure is found in Muelleria, Scoliopleura and Neidium.


Van de Vijver, B., Mataloni, G., Stanish, L. and Spaulding, S.A. (2010). New and interesting species of the genus Muelleria (Bacillariophyta) from the Antarctic region and South Africa. Phycologia 49: 22-41. 10.2216/09-27.1