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BFNA Title: Tomentypnum |
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Tomentypnum --
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, and by modern usage
to pleurocarpous moss Jean Faubert Camptothecium sect. Tomentella Kindberg, Eur. N. Amer. Bryin. 1 :86. 1897; Homalothecium subgen. Tomentypnum (Loeske) H. Robinson [as "Tomenthypnum"] Plants robust, erect, forming loose to dense
peatland lawns 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; hyalodermis of small and thick-walled cells, central
strand present, cells of inner cortex thin-walled; paraphyllia absent,
pseudoparaphyllia foliose; conspicuously covered for entire length on one
side by rhizoidal tomentum, rhizoids smooth, sometimes warty-papillose at
base, abundant (sometimes reduced or absent) much branched, reddish brown;
rhizoids or rhizoid initials occurring abaxially on proximal part of costa of
stem leaves; 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 or just proximal to the leaf apex; laminal
cells long-linear to vermicular, cell walls incrassate, nodose, becoming
porose in proximal parts of the 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 dotted-striate, 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 lower 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 with reduced or no tomentum. These plants were at times
described as varieties of T. nitens
but are now considered phenotypes of harsh environments. Contrariwise, plants
with tomentum present around the whole circumferences 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 Tomentypnum occurs from lowlands to alpine summits
of high mountains, in swampy grounds, wetlands, and peatlands. The habitat
preferences of the two species, although quite distinct, do overlap to some
extent as suggested by the existence of a number of intermixed populations,
usually from moderately rich fens habitats (D. H. Vitt and C. D. Hamilton
1975; R. Gauthier 1987). One species, T.
nitens, is very common in boreal and Arctic-alpine areas of 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; rhizoids 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 rhizoids restricted to the proximal parts of the costa of
stem leaves, stems smooth. Leaves
falcate-secund, distal portions often twisted, narrowly ovate-lanceolate,
gradually narrowed to slender acuminate apex, widest above bases, slightly
narrowed to insertion. The shape of
the leaves bases 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 Capsules
mature early to mid summer. Acidic,
oligotrophic environments, often associated with Sphagnum species on hummocks and peatland lawns; Greenland;
Alta., B.C., Man., N.B., Nfld. & Labr., N.W.T., N.S., Ont., Que., Sask.,
Conn., Maine, Mich., Minn., N.Y.; Asia (China, Siberia). 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 rhizoids occurring abaxially on the proximal portions of
the costa of stem leaves and also on the stems in 1(--2) transverse rows just
below leaf insertions. Leaves erect
to erect-spreading, straight,
tapering from the bases to a long-acuminate apex. Common and
widespread across boreal and arctic areas of the Northern Hemisphere,
reaching the high Arctic and extending south to Capsules
mature early to mid summer. Forming
lawns and hummocks in calcareous, mesotrophic fens in association with other
calciphiles; usually found with hypnaceous moss, 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, 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). OTHER REFERENCES
Gauthier R. 1987. La
répartition et l’habitat du Tomenthypnum falcifolium au Québec-Labrador. |
