A list of algae, mossy, pteridophytes and gymnosperm plant species to be included into the third edition of the Red Book of the Saratov region is proposed (1 species of algae, 15 mossy species, 13 pteridophytes, 1 gymnosperms). The necessity to correct and extend the protected taxon list in comparison with the second edition is substantiated. Principles of taxon selection for the third edition are discussed.
