XVI International Botanical Congess

Leucobryum is a remarkable moss genus due to the leaves being composed of leucocysts and chlorocysts. However, it is difficult to determine at the species level because of the wide range of variation shown by the leaves and leaf cells. At present about 100 taxa have been described from Asia and the Pacific. Yamaguchi(1993) reexamined the Asian taxa and recognized 19 species. However, the Pacific taxa are still insufficiently known. From 1997 to 1999 the Botanical Expeditions to the Hawaiian Islands were made by the National Science Museum, Tokyo. These Hawaiian and other collections have permitted a reexamination of the Pacific Leucobryum species. The Asian and Pacific region relationships of Leucobryum are discussed.