Re: BRYONET: Local endemic bryophytes

BRYONET
Very interesting question, local endemism.
There is a lot of 'species' known only from the type collection that
would fit into this category. BUT, all of them, like all very narrow
endemics in bryophytes (or better liverworts as I know them better) are
likely to be an artifact of lack of knowledge. I don't believe there is
any liverwort confined to 1-2 km² unless on a tiny island, and even
there I don't know of any example to quote.
Even if there are dispersal limitations in bryophytes (contrary to the
statements of some bryologists 20-30 years ago) living in such small
areas need some physical barrier, and even then it is a question if they
can have an enough large population to survive in the long run.
I do know of some plants that certainly have a very limited area (like
the silver tree Leucodendron argenteum on Table Mountain with a
distribution range of c. 1-2 x 0.1-0.2 km) but what would the mechanisms
be to have similar narrow ranges in bryophytes (unless it is the last
ones before extinction or the first ones after speciation).
Best wishes
Lars
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Lars Söderström
Professor
Department of Biology
NTNU
N-7491 Trondheim
Norway
ph. +47 73596061
fax +47 73596100


http://www.bio.ntnu.no/users/soder/
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