The genus Arthrorhaphis in the Himalayas,the Karakorum and the subalpine and alpine regions of south-eastern Tibet

Abstract

The yellow coloured taxa of the genus Arthrorhaphis (i.e. A. alpina var. alpina, A. alpina var. jungens, A. citrinella and A. vaci/lans) have been revised for the Himalaya Range, the Karakorum and for the south-east Tibetan fringe-mountains. Arthrorhaphis alpina var.jungens, usually growing on sandy soi!, appears to be a rather abundant lichen on open alpine (Kobresia) meadows, often associated with other weakly calciphilous crusts, such as Megaspora verrucosa, Phaeorrhiza nimbosa, Ph. sareptana, Psora decipiens and several Toninia species. Arthrorhaphis vacil/ans, with generally similar ecological requirements, and A. alpina var. alpina in more sheltered localities, are less frequent. Arthrorhaphis citrinel/a, growing on mosses or decaying plants rather than over pure soi!, is much more scarce in the study area than in the European