Himalamintha (Lamicaeae, Nepetoideae, Mentheae, Menthinae) a new genus from the Himalayan region

Himalamintha is described as a new genus in subtribe Menthinae characterized in first place by a calyx that is tubular and only weakly bilabiate, not sigmoid and distinctly bilabiate. The new genus contains 6 rather poorly known species occuring throughout the Himalayan region from the Chinese Province of Yunnan in the East to the western Himalayan foothills of Pakistan in the West. They had been placed in no fewer than 6 different genera over time (Calamintha, Clinopodium, Melissa, Micromeria, Satureja or even Thymus), whereas more recently they were united under Clinopodium. The species form a well supported phylogenetic lineage dissociated from typical Clinopodium and the other genera. It is more closely related to Ziziphora in the plastid DNA analyses or Cyclotrichium, Mentha and the Clinopodium abyssinicum group (also not close to typical Clinopodium) in the nuclear ribosomal DNA analyses. An overview on the complex taxonomic history is provided, morphological differences to related groups are outlined and the biogeography is discussed. Revising the material available from herbaria, literature and online databases, the genus and its component species are described in detail and an identification key is provided. For each species full synonymy, types and typifications are cited and the 5 names Calamintha barosma W.W.Sm., Calamintha euosma W.W.Sm., Clinopodium longicaule Benth., Micromeria wardii C.Marquand & Airy Shaw, and Thymus piperitus D.Don are typified. Notes on the species´ flowering time, ecology, altitudinal range, and distribution are added. Finally, images of the types and other herbarium specimens (incl. images of details), living plants and line drawings of diagnostic calyx characters are intended to support species identification.