The Old World species of Boehmeria (Urticaceae, tribus Boehmerieae). A taxonomic revision

This is the second part of a world-wide revision of the genus Boehmeria, the previously-published part having dealt with the New World species. The Old World species are widely distributed in the tropics and subtropics from West Africa to islands in the Pacific Ocean and from Japan and China to Southern Africa, Madagascar and Australia, with the highest species richness in the Himalayas and their extension into China and Indochina. No indigenous species is common to both the Old and New World. The species represent taxonomic units of very different complexity: most species exhibit little infraspecific variation; in several others formal taxonomic infraspecific units can be recognised; however, in two, B. virgata and B. japonica, a highly complex variation is seen, fitting with difficulty into the normal hierarchy of taxonomic classification. With the conclusions reached here, 33 species, including 31 varieties, are recognised and over one hundred previously established names are placed in synonymy. Four new taxa are described: B. pilosiuscula var. suffruticosa, B. virgata subsp. macrophylla var. minuticymosa, B. virgata subsp. virgata var. velutina and B. virgata subsp. virgata var. maxima. The following new combinations are made: B. densiflora var. boninensis, B. heterophylla var. blumei, B. japonica var. silvestrii, B. japonica var. tenera, B. sieboldiana var. fuzhouensis, B. ternifolia var. kamley, B. virgata subsp. macrophylla, B. virgata subsp. macrophylla var. canescens, B. virgata subsp. macrophylla var. densiglomerata, B. virgata subsp. macrophylla var. longissima, B. virgata subsp. macrophylla var. macrostachya, B. virgata subsp. macrophylla var. molliuscula, B. virgata subsp. macrophylla var. rotundifolia, B. virgata subsp. macrophylla var. scabrella, B. virgata subsp. macrophylla var. strigosa, B. virgata subsp. macrophylla var. sumatrana, B. virgata subsp. macrophylla var. tomentosa and B. virgata subsp. virgata var. austroqueenslandica.