*1: Mousehole Cave,
1888, RVT (B) (Paton 1969a:
717).
*2: Trewarmett, 1958,
TL (Paton 1969a: 717). [Older record (Camel R., in Tellam
1888) said not to be supported by specimen (Paton 1969a: 717)
but there may be one at OXF, see
below].
Most Cornish material of D. pellucidum s. l. and s. str. and D. flavescens needs to
be revised on the basis of the gametophyte characters
described by Werner (2002). There are no records of
sporophytes in Cornwall, and it was assumed for many years
prior to publication of Werner's study that non-fertile plants
could not be reliably separated (e.g. Corley & Hill 1981:
136, Newton in Hill et
al. 1992: 132). Consequently, all records prior to the
paper by Werner (2002) are placed as D. pellucidum s. l. unless specimens
have subsequently been revised. Nevertheless, identifications
using different gametophyte characters described by Werner
sometimes appear to contradict each other, so the last word
may not have been written on determination of non-fertile
material or indeed on whether two species are worthy of
recognition. Patricia M. Eckel (in Flora of North America
27: 384, 2007) treats flavescens as a
synonym of D. pellucidum. InCornwall
there does not appear to be any evidence of ecological
differences between the two taxa.
Grows in small patches (low lawns). Notes on
habitats of the s. l. species were
recorded as follows. On rock part-shaded on slope above track
at edge of deciduous woodland. Thin silt on boulders and a
slaty outcrop in flood-zone beside R. Tamar, in open and
lightly shaded by deciduous trees. Locally plentiful on thin
soil over old concrete of runway edges of disused airfield on
Davidstow Moor, with associates including Bryoerythrophyllum
recurvirostrum, Bryum argenteum, Bryum dichotomum, Didymodon nicholsonii.
Minster Church: on
damp vertical masonry on north wall of church and large plants
forming lawns on flat horizontal top of mortared wall south of
church. Thin damp soil of crevices in path at woodland edge,
part shaded. See also records under two segregate spp.
below.
Not seen c.fr.
