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Papanikolaou, 1985), while in the Baetic ranges of Spain the centres of endemism
are distinguished on the basis of the substrate (calcareous and siliceous) (Mota
et al.,
2002). Despite the problems in comparing the endemism rate among different
mountain ranges in Europe, Favarger (1972) concluded that the southern mountains
have a higher percentage of endemism (30-40%) than the northern ones (12-18%).
The author suggests this is probably due to:
a north-south gradient reflecting more favourable climate conditions;
a comparatively minor influence of glaciation in southern European mountains,
providing refugia for species that have become extinct elsewhere;
the high proportion of species that central European mountains have in com-
mon.
There are 405 endemic species in the Greek mountain flora (above 1500 m)
(Strid, 1986; Strid and Tan, 1991). On Mount Olympus, for example, there are ap-
proximately 150 species above 2400 m, half of which are endemic to the Balkan
peninsula with a dozen of those confined to Olympus (Strid, 1995).The flora of the
Cretan mountains is considered to be poor in absolute number of species (217 taxa),
compared to the remaining mountainous regions in Greece, as a result of the dry and
harsh conditions. However, there are 132 plant species endemic either to Greece
or the Cretan area occurring in the Lefka Ori massif. Strid (1995), discussing the
phytogeographical elements in the mountain flora of Greece, emphasizes the im-
portance of the Cretan mountains as refuges of endemism. Both regional and local
endemism in Greece increase in a southerly direction, culminating in the Lefka Ori
of western Crete, which displays one of the highest rates of narrow endemism in
the Mediterranean area.
In particular, gorges and the treeless mountain summits are very rich in endemic
species. In the mountains of Crete inaccessible cliffs and gorges support a rich en-
demic chasmophytic flora, which includes
Campanula jacquinii, Dianthus frutico-
sus, Ebenus cretica
and
Origanum dictamnus
. The high mountain areas of Lefka
Ori contain an equally important endemic element, with rare and localized species
including
Myosotis solange, Centaurea baldacii, Nepeta sphaciotica
and
Ranuncu-
lus radinotrichus
(Turland
et al.
, 1993). In Corsican mountains, although the overall
flora is species poor, there are 154 endemic taxa many of which have affinities with
alpine-arctic species, dating probably from the late Tertiary (Mouillot
et al.,
2008).
Mountain-top areas throughout the Mediterranean Basin are refuges for relict
conifer tree species (e.g. circum-Mediterranean fir species) as well as for geneti-
cally valuable, isolated populations of tree species whose core distribution is lo-
cated at higher latitudes in temperate regions (e.g.
Pinus sylvestris
).
Abies pinsapo
is a relict species that belongs to the group of circum-Mediterranean fir species,
and is endemic to the region on both sides of the Strait of Gibraltar. It forms iso-
lated populations above altitudes of 1000-1200 m on north-facing slopes in coastal
mountain ranges of southern Spain (West Baetic range) and northern Morocco (Rif
mountains) (Radford
et al.,
2011).
