GMPHIS SCRIPTA - Universitetet i Oslo

12 Hdkon Holien
Figure 1. Lecanora cinereofusca. Holien 6262 (TRH). Scale 1 mm.
known distribution in Europe is shown in Figure
2.
Outside Europe L. cinereofusca occurs on
both the Pacific and Atlantic coasts of North
America as well as in the Appalachian mountains
(Magnusson L932, Brodo 1984). Brodo
(I97 6) also lists records from eastern Asia
(mountains of the Philippines and northern
Japan), but it is not said to be present in Japan
by Miyawaki (1988).
Ecology
Lecanora cinereofusca is a species of smooth
barked trees. Its most common phorophyte in
Norway is Alnus incana, but it has also been
recorded on Prunus pa.dus, Quercus sP-, Salix
caprea, and Sorbus aucuparia. It has not been
found on Picea abies.
In the Alps it seems to prefet Fagus sylva'
tica; other phorophytes include Acer, Alnus and
Salix, more rarely also on Abies (Schauer 1965,
Schauer & Brodo 1966, Wirth 1995). In the
GRAPHTS SCRTPTA 8 (1997)
British Isles it has been found on Salix
(Hawksworth & Dalby 1992).
In Norway, L. cinereofusca is exclusively
confined to strongly oceanic localities (annual
precipitation
wet days
continuity. Typical habitats in central Norway
are slopes on marine sediments by rivers at low
altirudes. Such slopes are often dominated by
Alnus incana and are usually too unstable for
Picea abies to establish and compete successfutly.
All Norwegian finds are from the southern
boreal subzone or the lowland belt of the coastal
section (cf. Datrl et al. 1986, Moen 1987) and it
is treated as a southern rainforest species in the
boreal rainforests of central Norway by Holien
& Tonsberg ( 1996) . Lecanora cinereofusca
occurs with several other threatened lichens in
species rich epiphytic communities . Pseudoqphellaria
crocata has been recorded from all
except one of the Norwegian localities. More or
less faithful accompanying crustose lichens
include Arthothelium norvegicum, Bacidia absis