Chenopodium pamiricum (Amaranthaceae) and Allied Species in Asia: The Prolonged Misapplication of Names

Up to the late 1990s and early 2000s, several small-leaved species of Chenopodium (Amaranthaceae s. lato/Chenopodiaceae s. stricto) were frequently misnamed in floras of central Asia and Siberia. Two widespread taxa, C. prostratum (now accepted as C. karoi) and C. vulvaria, were commonly recognized. However, the latter is absent from Siberia and occurs only in the southwestern central Asia. Further north the name ‘vulvaria’ was misapplied to two species, C. pamiricum and C. grubovii Lomon. & Uotila sp. nova, characterized by procumbent stem branched mostly basally and entire, ovate leaf blade. Chenopodium pamiricum, distinguished by erect stem branched along the whole length and trilobate to entire, trullate leaf blade, was earlier often known by the synonymous name C. iljinii and misapplied to C. grubovii. They can be distinguished from C. vulvaria and C. karoi by their deeply divided perianth lobes and broadly ovate seeds; from each other they mostly differ in the growth habit and leaf characters. Chenopodium karoi is very widely distributed, from the Hindu Kush and the Himalayas to northern and northeastern Asia, C. pamiricum and C. grubovii occur on high mountains from the Hindu Kush, Pamir, and western Himalayas as far as southern Siberia, Mongolia, and central and western China, the latter species being more common in the north. Chenopodium grubovii grows at higher elevations than C. pamiricum and both species usually grow at higher elevations than C. karoi. A key, descriptions, drawings, and distribution maps for these species are provided.