Family Cruciferae Juss. (Brassicaceae Burnett) of SAKHA (Yakutia) Republic

The paper offers a new revision of the species composition of the Cruciferae family in Yakutia, which is supplemented by information on the geographical distribution and taxonomic composition. In the present work, the crucifers of Yakutia are represented by 39 genera and 102 species. Among them, there are two endemic species (Boechera falcata (Turcz.) Al-Shehbaz and Smelowskia jacutica (Botsch. et Karav.) Al-Shehbaz et Warwick), and one subendemic (Isatis jacutensis (N. Busch) N. Busch). Traditionally, the genus Draba is the richest in the number of species in the territories reaching into the Arctic. At present, taking the latest processing of the genus by V. V. Petrovsky (Petrovsky, 2018) into account, it numbers 32 species, which amounts to about 1/3 of the total species richness of this family in Yakutia. The paper summarizes the nomenclature changes that have affected a number of representatives of this family in recent years, and proposes new combinations in the genus Boechera (B. pendula (L.) V. I. Dorof. Comb. Nov.) and Thellungiella (T. bursifolia (DC.) V. I. Dorof. Comb. Nov.). An analysis of the diversity of crucifers made it possible to assert that the flora of Yakutia is obviously insufficiently studied in its northwest and northeast reaches, and to suggest that the floristic zoning of Yakutia should be supplemented by outlining three supra-regions, namely the Verkhoyansk (eastern), Vilui (western) and Arctic (northern) supra-regions.