Vascular plants of Azerbaijan: a nomenclatural update and survey of Lamiaceae L. | Lamiaceae species in Azerbaijan

Lamiaceae (Labiatae) is the fourth largest angiosperm family in Azerbaijan flora. Previous taxonomical studies on Lamiaceae were mainly based on morphological characters. But latest molecular studies on the phylogeny of the Lamiaceae shed light towards understanding, clarifying borders of and relationships among its genera. The aim of our study was to nomenclatural updates and classification of Lamiaceae species distributed across Azerbaijan. The family is represented by 37 genera, 241 taxa (204 (native and introduced) species, and 37 subspecies) of which 19 taxa are endemics. 4638 herbarium specimens of BAK and 1245 specimens from various virtual herbaria have been analyzed. 46 new taxa were added as a supplementary to the VII volume Flora of Azerbaijan after its publication. According to the most recent classification, a new monotypic genus Drymosiphon Melnikov is revealed within subfamily Nepetoideae of the Lamiaceae in Azerbaijan. And also in the context with the latest taxonomic reconstructions Vitex L. from Verbenaceae Juss. is transferred into subfamily Viticoideae Briqone within the Lamiaceae. The largest three genera according to taxon number are Salvia L. (38 taxa), Nepeta L. (30 taxa), and Stachys L. (25 taxa). Mountain part of Nakhchivan (62 taxa), Diabar (58), Guba part of the Greater Caucasus (37) are the most species-rich and genera-rich botanical-geographical regions. The phytogeographic regions with the highest taxon number are Irano-Turanian (88 taxa (37%)), Euro-Siberian (42 taxa (18%) and Caucasian (39 taxa (16%)) regions.12 taxa are in threatened categories (CR-4, EN-1, and VU-7) and 12 are near threatened (NT) according to IUCN. 7 species are listed in the 2nd edition of Red Book of Azerbaijan. After current nomenclatural updates, the result proved that Azerbaijan with its landscape and habitat diversity plays a significant role in speciation of the Lamiaceae family in the Caucasus.