Paper presents a nomenclature-taxonomic revision of the flora of marine macrophytes of nature reserves of the Crimean Peninsula based on the results of original studies and literature data. During the one and a half-century period of observations in the coastal-marine areas now included in Crimean nature reserves, 240 taxa of macrophytes (both of species and intraspecific rank) were recorded, which makes up 53% of the flora of the Azov-Black Sea basin. They belong to 5 divisions, 9 classes, 34 orders, 62 families, and 120 genera of algae. Rhodophyta especially stands out because of its taxonomic diversity. Marine macroflora in nature reserves varies in species richness from 191 species found in Karadagsky NR and 154 in Cape Martian to 97 species cited for Swan Islands, 84 for Opuksky, and 73 species found in Kazantipsky NR. The rare taxa fraction consists of 49 species in total; Cape Martian (39 taxa) and Karadagsky (37) NR are the richest in its representatives. In the coastal areas of studied reserves, a number of biotopes under the special protection of the EU Habitats Directive are located (Council Directive 92/43/EEC). All mentioned NR are structural elements of the Emerald Network, four of them designated as Wetlands of International Importance. The main threat to the natural phytodiversity of the Crimean NR marine areas is the anthropogenic transformation of biotopes. Also, there is a problem associated with the change of the borders and the status of some protected objects. The data obtained indicate that Crimean NRs remain a key link in the system of conservation of natural phytodiversity and maintaining the ecological balance in one of the most densely populated areas of Eastern Europe.
Keywords: macrophytobenthos, flora, nature reserves, Crimean Peninsula, Black Sea, Azov Sea