Taxonomic revision of Chenopodiaceae in Himalaya and Tibet.

The composition of many Chenopodiaceae genera in different parts of Himalaya and Tibet has been insufficiently known or contradictory. A revision of the family in Himalaya including Bhutan, Nepal, parts of India (Himachal Pradesh, Jammu and Kashmir, Sikkim and Uttarakhand) and Tibet (Xizang, China) is presented for the first time. Altogether, 57 species from 20 genera are reported, including three species new to science (Agriophyllumtibeticum, Salsolaaustrotibetica and Salsolahartmannii). Atriplexcentralasiatica, Corispermumdutreuilii and Salsolamonoptera are identified as new records for India and Chenopodiumpamiricum is recorded in China for the first time. Dysphaniaambrosioides and Sympegmaregelii are recorded for Xizang. The generic and species keys, species distributions (including maps) and taxonomic notes are provided. We indicate for the first time that the presence of short yellow hairs is the remarkable morphological characteristic of the genus Grubovia. Evident heterocarpy and heterospermy is found in Dysphania for the first time (Dysphaniatibetica). Agriophyllumpungens, Atriplexcrassifolia, Atriplexlaciniata, Atriplexsagittata, Axyrisamaranthoides, Axyrishybrida, Bassiaindica, Corispermumkorovinii, Dysphaniaschraderiana (=Chenopodiumfoetidum auct.), Halocharisviolacea and Suaedamicrosperma are excluded from the species list. Neobotrydiumcorniculatum is synonymised with Dysphaniakitiae, Neobotrydiumlongii with Dysphaniahimalaica and Neobotrydiumornithopodum seems to be conspecific with Dysphanianepalensis. Corispermumladakhianum is a new synonym of Corispermumtibeticum. Amaranthusdiandrus is added to the synonyms of Acroglochinpersicarioides, and Bassiafiedleri, previously considered as conspecific with Gruboviadasyphylla, is added to the synonymy of Bassiascoparia. Lectotypes of Anabasisglomerata (≡Halogetonglomeratus), Halogetontibeticus (=Halogetonglomeratus), Amaranthusdiandrus (=Acroglochinpersicarioides), Chenopodiumtibeticum (≡Dysphaniatibetica), Corispermumdutreuilii, Corispermumfalcatum, Corispermumlhasaense, Corispermumpamiricumvar.pilocarpum (=Corispermumgelidum, syn. nov.), Corispermumtibeticum, Kochiaindica(≡Bassiaindica), Kochiaodontoptera (≡Bassiaodontoptera) and Salsolamonoptera are selected. Out of 53 native elements, 42 are restricted in their distribution to Himalaya and Tibet at altitudes 2000-4500 m above sea level. The greatest taxonomic diversity of the Chenopodiaceae is represented in Jammu and Kashmir (India) and Xizang (China) with a continuous decrease in the number of species southwards.