BFNA Title: Tomentypnum
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]
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.
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
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).
widespread across boreal and arctic areas of the Northern Hemisphere,
reaching the high Arctic and extending south to
1987. La répartition et l’habitat du Tomenthypnum
falcifolium au Québec-Labrador.