BRYONET
Lars is right - there are MANY examples of species only known from the
Type locality.
Descriptions of these species have been based on morphological
differences (often very minor) and geographical isolation. Who knows
what will happen if we start applying molecular genetic analysis to such
species.
One hepatic which might meet the requirements of very restricted
occurrence is Seppeltia succuba (immature female plants only are known),
described by Riclef Grolle from collections I made on Macquarie Island,
an isolated subantarctic island. The island itself (54 S, 158 E) is
34km x 2-5km, is very isolated in the southern ocean, and has never been
connected geologically to any land mass. It is a piece of the earth's
crust that has been elevated above the surface of the ocean at the
confluence of two tectonic plates. I know of Seppeltia from three very
local sites on the eastern side of the island (each less that 300m from
the other) and from one site on the west coast, approximately 10km distant.
BUT. A few years ago, David Glenny located the species from one remote
site in the South Island of New Zealand. The tantalising thing is that
a molecular analysis would be very useful, but I am the only one who has
ever found the taxon on Macquarie Island and am not likely to get back
there. Extracting DNA from the Type or isotype collections would not be
impossible, but in total there is not a great amount of material.
A further candidate might be the Sphagnum-related and unique
(molecularly and morphologically) Ambuchanania leucobryoides, described
by Howard Crum and me but found in a very restricted part of the south
west coast of Tasmania. Recently it was located in another quite
separate site. Jon Shaw (Duke University) has been doing a lot of work
on the molecular genetics of this.
Personally, I am always suspicious of localised endemics and I daresay
that molecular analysis will show that many of these are geographical
variants of other taxa.
Prof Rod Seppelt
Principal Research Scientist
Australian Antarctic Division
203 Channel Higway
Kingston, Tasmania, 7050
Australia
Ph +61 (0)3 6232 3438
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