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BFNA Title: Tomentypnum |
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Amblystegiaceae
-- Tomentypnum XXX.
TOMENTYPNUM Loeske, Deutsch. Bot. Monatsschr. 22 : 82. 1911 * [Latin, tomentosus felty, refering to the
felted rhizoids, and Greek, hypnos,
sleep, in antiquity applied to various mosses or lichens] Jean Faubert Camptothecium sect. Tomentella Kindberg, Eur. N. Amer. Bryin. 1 :86. 1897; Homalothecium subgen. Tomentypnum (Loeske) H. Robinson Plants robust, erect, forming loose to dense turfs
or hummocks, golden to yellow-green
or golden-brown, glossy when dry. Stems (4--)5--9(--13) cm; pinnately or
subpinnately branched in one plane, branches horizontal, straight to arcuate;
epidermis of small and thick-walled cells, central strand present, cells of
inner cortex thin-walled; paraphyllia absent, pseudoparaphyllia foliose;
rhizoids smooth, sometimes warty-papillose at base, abundant (sometimes
reduced or absent) much branched, reddish brown forming
a conspicuously tomentum over the entire length of one side of the stem; rhizoids or
rhizoid initials on stem and abaxially on costa, smooth, strongly branched
(often forming tomentum);
axillary hairs 2--5(--6)-celled. Stem
leaves crowded, erect to
erect-spreading, straight or falcate-secund, little changed when wet, long-lanceolate,
slenderly acuminate, non-decurrent, strongly plicate, (2--)2.5--4 mm; margins
plane or narrowly and tightly recurved, entire or sinuose; costa single,
ending near the leaf apex; laminal cells long-linear to vermicular, cell
walls incrassate, nodose, becoming porose in proximal parts of leaves; one or
two rows of shorter and sometimes colored cells at insertion; alar cells not
or scarcely different from other cells at leaf insertion. Branch leaves smaller but otherwise
little different from stem leaves. Specialized
asexual reproduction not seen.
Sexual condition dioicous, often sterile; perichaetial leaves
long-lance-subulate, to 7 mm, strongly plicate, margin entire, costa single
and ending far beyond mid leaf; paraphyses present on vaginula. Seta 2.5--4.5(--5) cm, smooth,
straight to somewhat flexuose, slightly twisted when dry, reddish brown,
darker below, lighter above. Capsule
inclined to horizontal, smooth, oblong-cylindric, arcuate, contracted below
mouth when dry, neck short, wrinkled when dry; stomates few, long-pored;
annulus separating, of 3--4 rows of cells; operculum conic to long-conic,
apiculate; peristome perfect; exostome teeth lanceolate, basally reticulate,
distally papillose, bordered and trabeculate, brownish yellow; endostome with
high basal membrane, segments narrowly split along midlines, cilia 2--3(--4),
well developed, nodulose. Calyptra
cucullate, naked. Spores 12--18
µm, granulose to minutely papillose. Species 2 (2
in the flora): widely distributed in the Holarctic. The major
characters of Tomentypnum are the
erect habit, thick rhizoidal tomentum on one side of stem, presence of
rhizoids on the proximal abaxial surface of the costa, strongly pluriplicate
leaves, absence of clearly differentiated alar cells, and the presence of a
stem central strand that can vary from sharply defined to barely discernible
on the same stem. However, in Arctic-alpine environments, plants of both
species will be found without tomentum or with reduced tomentum. These plants
were at times described as varieties of T.
nitens but are now considered phenotypes of harsh environments.
Contrariwise, plants with tomentum around the whole circumference of the
stems are sometimes encountered. Shape of the leaves is the major character
separating the two species. As pointed out by R. Gauthier (1987), some
variability in the curvature of the leaves is occasionally present on some
plants but atypical leaves are usually localized to a few branches or to a
sector of the stem. There is little difference in size of leaves or stems
that can be used to separate the two species. Sporophytes are uncommon. An
invalid orthographical variant ("Tomenthypnum")
is widely used in SELECTED
REFERENCES Vitt, D. H. and C. D.
Hamilton. 1975. Taxonomic Status of Tomenthypnum
falcifolium. Bryologist 78: 168--177.
Vitt, D. H., T. Cao, M. K. Campenot and R. Gauthier. 1990. The genus Tomentypnum in north-east 1. Leaves
falcate-secund, often twisted in their distal portions, widest just above the
base; rhizoid initials restricted to proximal portion of stem leaves, stems
smooth; usually in Sphagnum-dominated vegetation . . . . 1. Tomentypnum falcifolium 1. Leaves
straight, not or little twisted in their distal portions, widest at base;
rhizoids initials on proximal portion of stem leaves and on stems just below
leaf insertions; rich fens . . . . 2. Tomentypnum
nitens 1. Tomentypnum falcifolium
(Nichols) Tuomikoski
in Ahti & Fagerstén, Ann. Bot. Fenn. 4 : 435. 1967 Camptothecium nitens var. falcifolium Nichols, Rhodora 15 :12, 1913; Homalothecium nitens var. falcifolium (Nichols) Wijk & Margadant; Tomentypnum nitens var. falcifolium (Nichols) Podpěra Stems smooth, rhizoids restricted to the proximal part of stem
leaf costa. Leaves falcate-secund,
distal portions often twisted, narrowly ovate-lanceolate, gradually narrowed
to slender acuminate apex, widest above base, slightly narrowed to insertion. Capsules
mature early to mid summer. Acidic,
oligotrophic environments, often associated with Sphagnum species on hummocks and turfs; Greenland; Alta., B.C.,
Man., N.B., Nfld. & Labr., N.W.T., N.S., Nunavut, Ont., Que., Sask.,
Conn., Maine, Mich., Minn., N.Y.; Asia (China, Siberia). The shape of
the leaf base is best observed while the leaves remain attached to the stem. Tomentypnum falcifolium is widespread
but more sporadic than T. nitens,
occurring across the boreal and sub-Arctic areas of 2. Tomentypnum nitens (Hedwig) Loeske, Deutsch. Bot. Monatsschr. 22: 82. 1911 Hypnum nitens Hedwig, Sp. Musc. Frond. 255. 1801; Camptothecium nitens (Hedwig)
Schimper; Homalothecium nitens (Hedwig) H. Robinson; Tomentypnum nitens var. involutum (Limpricht) C. E. O. Jensen Stems with rhizoides in 1(--2) transverse rows just below leaf
inservations, rhizoids also occurring abaxially on the proximal portions of
stem leaf costa. Leaves erect to erect-spreading, straight, tapering
from the bases to a long-acuminate apex. Capsules
mature early to mid summer. Forming
turfs and hummocks in calcareous to intermediately mineral-rich, mesotrophic
in association with other calciphiles, usually found with mosses such as Paludella squarrosa and species of Aulacomnium; Greenland; St..Pierre and Miquelon; Alta., B.C.,
Man., N.B., Nfld. & Labr., N.W.T., N.S., Nunavut, Ont., Que., Sask.,
Yukon; Alaska, Calif., Colo., Conn., Idaho, Ill., Maine, Mass., Mich., Minn.,
Mont., N.H., N.J., N.Mex., N.Y., N.Dak., Ohio, Oreg., Pa., Utah., Vt., Wash.,
W.Va., Wis., Wyo.; n and c Europe; n Asia; Atlantic Islands (Iceland);
Pacific Islands (Aleutian Islands). Common and
widespread across boreal and arctic areas of the Northern Hemisphere,
reaching the high Arctic and extending south to OTHER REFERENCES
Gauthier R.
1987. La répartition et l’habitat du Tomenthypnum
falcifolium au Québec-Labrador. |
