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In this volume twenty-three species of Neidium are described. Sample materials were collected in the Zoigê Wetland, an expansive network of lakes and wetlands located in Sichuan Province, China. From the total number of Neidium species reported, sixteen of them are described as new. 281 light microscope and scanning electron microscope photographs document all taxa and illustrate the morphology of these Neidium species. Detailed descriptions for each species are given and the species are compared with other, similar species from other regions of the world. The variability in valve morphology in the genus, including presence and distribution of renilimbi, longitudinal canals, central nodule and striation, are documented. A comprehensive table with morphometric details of all described Neidium species rounds up the volume. This survey of Neidium species almost doubles the number of new Neidium taxa described from China and is of interest for all readers working on diatoms and Bacillariophyceae.

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