The vars. of this sp. are only identifiable on the
rather infrequent occasions when they bear capsules and have
perichaetial bracts that survive with uneroded apices, so all
records of non-fertile plants and some of fertile plants are
referred only to F. squamosa s. l.
Grows as wefts, 5-20 cm or not infrequently up to
25 cm long. Notes on its habitats in Cornwall are as follows.
Attached mainly to rocks (granitic, slaty), but also masonry,
concrete, stable gravel, firm hard soil or wood, trailing in
shallow water (to 20 cm depth) or hanging where intermittently
inundated (up to 20 cm above water level). It grows in
soft-water streams and rivers, usually where ± quick-flowing,
but is also widespread in winter-flooded zones at edges of
Drift, Stithians and Siblyback Reservoirs (mainly in places
exposed to wave action). It grows in the open, lightly shaded
or sometimes in rather heavily shaded places.
The present species is restricted to soft water,
unlike F. antipyretica (see
above), and mainly found in well oxygenated quick-flowing
water. In middle reaches of R. Tamar F. squamosa grows mainly
where permanently submerged, whereas F. antipretica
withstands more desiccation and occurs alongside it up to 0.7
m above low summer water levels. In contrast, where F. squamosa occurred
with F. antipretica at Drift
Reservoir the latter species was much more plentiful and more
widespread, occurring in deeper water and more sheltered
sites. In a stream near Cape
Cornwall
it was recorded as extending downstream to near the
shore.
Fontinalis squamosa mostly occurs in pure patches but its associates
sometimes include Chiloscyphus
polyanthos, Fontinalis
antipyretica var. antipyretica, Hygrohypnum ochraceum,
Platyhypnidium
riparioides, Scapania undulata,
lichens, less often Leptodictyum riparium,
Fissidens fontanus,
Platyhypnidium
lusitanicum, Thamnobryum
alopecurum.
Occasionally c.fr.: capsules immature [3], 8;
dehiscing 8; dehisced 4, 7, 8.
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