Floristic survey of Karaginskii Island (southwest Bering Sea) revealed predictably high diversity of aquatic plants and unexpectedly overlooked terrestrial species

Given the high diversity of aquatic habitats with favorable microclimate, surprisingly low number of aquatic vascular species was reported from Karaginskii Island. Therefore, we conducted its extensive field inventory. Terrestrial and bog plant species were also registered on the island whenever possible to check for general completeness of floristic knowledge. We also performed preliminary survey of aquatic flora of adjacent mainland as a reference. We revealed 26 aquatic vascular taxa, new for the flora of Karaginskii Island among which 17 were new to the Karaginskii District. Ten of them were also found on the adjacent mainland; 6 taxa revealed only on the mainland were new for the Karaginskii District. We found 27 terrestrial and bog vascular species, new for the island flora (14 new for the Karaginskii District). The documented deficiency of data on northern Kamchatka (Koryakia) flora hampers informed protection of endangered species and prevents sound biogeographic zonation of Kamchatka.