New discoveries in the lichen genus Staurolemma Korber
Jørgensen, Per M.
Three further species are added to the genus Staurolemma, viz. S. oculatum P.M.Jørg. & Aptroot from China, S. orbiculare P.M.Jørg. & Aptroot from Australia and S. perforatum P.M.Jørg. from Japan and Korea, the genus thus adding up to eight species. The genus falls in two distinct groups, one of which, viz. subg. Hymenolemma P.M.Jørg., is newly described. It has membranaceous, often fenestrate thallus and I- walls of the asci. The type species of this subgenus is S. dussii (Vain.) P.M.Jørg. & Henssen. This species is recorded as new to Asia, from Sri Lanka. A key to all known species of Staurolemma is given. These new discoveries give further support to the former hypothesis that this genus might be an old element in our lichenflora, as it proves to have most species in Australasia with strong links to the Southern Hemisphere. Particularly interesting in this connection is the discovery in Australia of S. orbiculare, a very close relative of the generic type species, S. omphalarioides from Europe, the recorded presence of which in SE Asia proved incorrect.