Taxonomic revision of Chenopodiaceae in Himalaya and Tibet

Abstract

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,SalsolaaustrotibeticaandSalsolahartmannii).Atriplexcentralasiatica,CorispermumdutreuiliiandSalsolamonopteraare identified as new records for India andChenopodiumpamiricumis recorded in China for the first time.DysphaniaambrosioidesandSympegmaregeliiare 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 genusGrubovia. Evident heterocarpy and heterospermy is found inDysphaniafor the first time (Dysphaniatibetica).Agriophyllumpungens,Atriplexcrassifolia,Atriplexlaciniata,Atriplexsagittata,Axyrisamaranthoides,Axyrishybrida,Bassiaindica,Corispermumkorovinii,Dysphaniaschraderiana(=Chenopodiumfoetidumauct.),HalocharisviolaceaandSuaedamicrospermaare excluded from the species list.Neobotrydiumcorniculatumis synonymised withDysphaniakitiae,NeobotrydiumlongiiwithDysphaniahimalaicaandNeobotrydiumornithopodumseems to be conspecific withDysphanianepalensis.Corispermumladakhianumis a new synonym ofCorispermumtibeticum.Amaranthusdiandrusis added to the synonyms ofAcroglochinpersicarioides, andBassiafiedleri, previously considered as conspecific withGruboviadasyphylla, is added to the synonymy ofBassiascoparia. Lectotypes ofAnabasisglomerata(≡Halogetonglomeratus),Halogetontibeticus(=Halogetonglomeratus),Amaranthusdiandrus(=Acroglochinpersicarioides),Chenopodiumtibeticum(≡Dysphaniatibetica),Corispermumdutreuilii,Corispermumfalcatum,Corispermumlhasaense, Corispermumpamiricumvar.pilocarpum (=Corispermumgelidum, syn. nov.),Corispermumtibeticum,Kochiaindica(≡Bassiaindica),Kochiaodontoptera(≡Bassiaodontoptera) andSalsolamonopteraare 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.