*1: Newlyn Cliff, 1866,
WC (PNZ) (Paton 1969a: 726).
*2: Rock near St
Minver, 1890, RVT (B) (Paton 1969a:
726).
Crundwell & Nyholm (1962) recognised glareicola as a
variety of T. flavovirens,
differing from the typical form in having larger leaf cells
(cells in upper part of lamina >12 µm), although they
acknowledged that some intermediates occur. They did not see
material of var. glareicola from
Cornwall. Paton (1969a: 726) treated the two forms together
'because it is often difficult to distinguish between them'.
Although a recent national checklist (Blockeel & Long
1998: 86-87) continued to recognise var. glareicola, recent
work in Cornwall shows that intermediate plants are very
common. Also, var. 'glareicola' has been
found on the same cliffs as var. flavovirens (e.g. on
gabbro rocks at Coverack), and they frequently occur close
together; 'var. glareicola' has also
been recorded alongside the typical form in short dune
grassland on calcareous sand (Penhale, Marazion, Upton
Towans). Hence, recognition of vars. is probably not
worthwhile and Smith (2004: 285) and Hill et al. (2008) treated glareicola as a
synonym of T. flavovirens.
Grows as cushions, patches or small low lawns.
Habitat notes from C&S are as follows. Essentially a
coastal species, growing on varied mineral soils including
calcareous sand and loams, thin soil layers over rocks and in
rock crevices (shales, slates, granitic, gabbro, greenstone
and serpentinite lithologies; also on old mortar), among old
metalliferous mine-spoil, and occasionally also on such humic
substrates as decayed Armeria maritima
tussocks. Often common in short dune grassland, on blown sand
on coastal hillslopes, in partly bare areas on rocky
sea-cliffs, including low cliffs near creeks, on 'hedges' and
banks above cliffs, and walls and wall tops near coast. Also
recorded from trampled grassland just above edge of saltmarsh,
and gravel among graves in coastal churchyard. Typically grows
fully insolated, or at most lightly or partly shaded. Normally
restricted to vicinity of coast, from HWST level upwards, but
occurring up to ca
1 km inland on sand-dunes. Found unusually far inland at
Holy Vale, St Mary's (one cushion on sheltered wall), where
700 m from nearest coast. Record from Gwithian churchyard
(small patch on old grave) was ca 750 m inland, but
not far from edge of dunes. Often in pure patches. On some
very sheltered creekside-cliffs occurs near HWST level, close
to Schistidium
maritimum. On more exposed cliffs commonly forms zone at
somewhat higher levels than S. maritimum with
associates that often include Didymodon tophaceus, Tortula viridifolia,
Trichostomum
brachydontium, Conocephalum
conicum.
No recent records c.fr. in Cornwall, and only female
plants have been noticed recently (with archegonia seen: 1, 9,
11, 12). Blockeel (in Hill et al. 1992: 321)
noted that capsules are very rare in Britain, but they were recorded
from Cornwall (Falmouth and Fowey, in spring) by
Dixon (1924:
242).