Timo Koponen

Solving the identity of the large Plagiomnium (Musci) from Madeira (Portugal): P. undulatum var. madeirense T. Kop. & C. Sérgio

Abstract A new variety of Plagiomnium undulatum (Hedw.) T. Kop. var. madeirense T. Kop. & C. Sergio is described from Madeira Island. The plants present an aquatic ecology and are characterised by broadly and longly decurrent leaves and by large size of laminal cells. This taxon is illustrated and the specimens studied are mapped.

ENDANGERED BRYOPHYTES ON A GLOBAL SCALE

Abstract The possibilities of survival of bryophytes belonging to major phytogeographical elements are evaluated. The arctic and boreal bryofloras are much less endangered than the temperate, meridional and tropical bryofloras. This is because many arctic and boreal taxa have wide and often circumpolar ranges and, in addition, outposts in the mountains of more southern areas. Most endangered are the taxa which inhabit special environments or substrates, as virgin forests, rotten wood or rivulets. There are, however, examples of total local disasters in the arctic and in the boreal forest zone due to pollution and mechanical destruction. The richest temperate, meridional and tropical bryofloras occur in forested areas, which are disjunct on different continents. There are examples of disjunct temperate and pantropical species of bryophytes, byt many taxa are endemic to certain separate ecosystems (e.g. on the west coast of North America, eastern North America, Europe, and east Asia). Most human cultivation is in temperate and meridional zones, and in many areas, notably in China, practically all forest has been cleared for agriculture. The temperate and meridional bryofloras can be saved only by conserving still existing forested areas. The richest bryofloras in the tropics occur in the tropical rain forests and especially in tropical montane forests. The present destruction of these forests by clear cutting means an almost total loss of their bryoflora. Only very few species of virgin tropical forests are able to survive in manmade habitats.

Bryophyte flora of Hunan Province, China. 12. Diphysciaceae (Musci).

The genus Diphyscium (Diphysciaceae, Bryophyta) has three species in the Hunan Province of China: D. fulvifolium Mitt., D. mucronifolium Mitt, and D. chiapense D.H. Norris subsp. unipapillosum (Deguchi) T.-Y. Chiang & S.-H. Lin. Diphyscium fulvifolium is clearly the most common species. The other two taxa are reported for the first time from Hunan, and D. chiapense subsp. unipapillosum also from Jiangxi; in China, it was previously known only from Taiwan. The three species are illustrated in line drawings. A previous record of D. foliosum (Hedw.) Mohr was based on a misidentified specimen and the species is thus excluded from the flora of Hunan.

Bryophyte Flora of the Huon Peninsula, Papua New Guinea. LXXI Merrilliobryum (Myriniaceae, Musci)

We report on New Guinea occurrences of the genus Merrilliobryum, previously thought to he endemic to the Philippines. The New Guinea plants are named M. tanianum D.H. Norris, T.J. Kop. & W.R. Buck, sp. nova. They differ from the Philippine M. fabronioides Broth. in their larger size, relatively broader leaves, the more elongate cells of the median leaf, and in the number of cells in the uniseriate leaf apex. The paper includes a key, descriptions, illustrations and distributional data for the two species of the genus.