During our investigation, 28 species belonging to the genus Sellaphora Mereschowsky were found in different types of water bodies and streams in Mongolia. Of these, 14 species have already been described and/or shown earlier in the flora of Mongolia, and we found 14 species for the first time. One new taxonomic combination has been proposed: Sellaphora glomus (J.R. Carter and A.E. Bailey-Watts) Glushchenko and Kulikovskiy comb. nov. One species is proposed for description as new to science: Sellaphora dorofeyukae Glushchenko and Kulikovskiy sp. nov. All species were illustrated with original light micrographs, and a number of species were also illustrated with scanning electronic photographs. The distribution of the identified species within Mongolia and the world is discussed.
Keywords: Bacillariophyceae; Mongolia; Sellaphora; morphology; new records; new species; systematics; taxonomy.