Dicranodontium asperulum Brotherus 1901

Sporophytes of Dicranodontium asperulum were seen in North America only in one British Columbia specimen. The wide-spreading leaves, standing out from the stem at 45° or more when wet, and the serrate to serrulate shoulders of the leaf bases make D. asperulum the most distinctive North American species of the genus. The leaves of the other species are appressed or weakly spreading when wet, with entire bases.

Plants small to rather large, up to 5 cm high, yellowish green, in weakly silky, loose or dense tufts. Stems erect or ascending, somewhat flexuose, unbranched or sparsely branched, radiculose below; central strand present. Leaves up to 7 mm long, homomallous, often deciduous, flexuose or falcate when dry, erect-spreading when moist, upper ones usually falcate-secund, abruptly narrowed from an ovate, convolute base to a very long, roughened, setaceous apex or often in semi-canaliculate awn; margins distinctly serrulate at shoulder, sometimes nearly to the base, often dentate near the apex; costa occupying ¼ – 1/3 the leaf base width, long-excurrent, often spinulose at tips, with several dentate ridges at back, occasionally nearly smooth; upper cells above the shoulders rectangular to linear, smooth or nearly so; upper basal cells in the sheathing base rectangular to linear, 30–50 µm × 10–20 µm, firm-walled; lower basal cells becoming broadly rectangular close to the costa, narrower near the margins, forming an indistinct marginal band; alar cells often inflated, broadly rectangular to subquadrate, 30–60µm × 20–30 µm, thin-walled, hyaline, fragile, occasionally forming indistinct auricles. Dioicous. Perichaetial leaves not much differentiated. Setae up to 1 cm long, yellowish, strongly flexuose when dry, cygneous when moist; capsules cylindric, 0.6–1.0 mm × 0.4–0.5 mm, brownish; opercula long-rostrate; annuli absent; peristome teeth lanceolate, ca. 0.3 mm long, divided unequally to the middle. Spores not seen.

Plants brown proximally, yellowish to dark green distally, dull to glossy, in loose tufts. Stems 1-6(-8) cm, radiculose proximally with whitish to reddish brown rhizoids. Leaves erect-patent, flexuose, spreading at ca. 45º or more when wet, occasionally falcate-secund at stem apices, 3-8 mm, often deciduous, abruptly narrowed from an ovate base into a setaceous subula, subtubulose proximally, channeled distally, margins serrulate to serrate at shoulders, usually strongly serrate distally, apex acute; costa distinct, occupying ca. ¹/3 of leaf base; cells not thick-walled or pitted, distal cells linear, 24-56 × 5-6 µm, basal cells broadly rectangular, hyaline, ca. 9 µm wide, alar cells sometimes forming indistinct auricles, hyaline. Seta 15-20 mm, erect-sinuose. Capsule 1.5-2 mm; operculum not seen, reportedly shorter than the capsule. Spores 9-14 µm.

Distrobution: China, Japan, Nepal, India, Europe, and North America.

Habitat: on rocks or rotten wood in subalpine forests.

Dicranodontium aristatum Schimp., Syn. Musc. Eur. 695. 1860. Dicranodontium capillifolium (Dix.) Takaki, J. Hattori Bot. Lab. 31: 292. 1968. Brothera capillifolia Dix., J. Bombay Nat. Hist. Soc. 39: 774. 1937. Synonymized by Frahm (1997).

Dicranum asperulum Mitten, J. Linn. Soc., Bot., suppl. 1: 22. 1859; Campylopus virginicus (Austin) Lesquereux & James; Dicranum virginicum Austin

Dicranodontium asperulum (Mitt.) Broth
Pfl. I 3 : 336. 1901.
Dicranum asperulum Mitt. Jour. Linn. Soc. 3: Suppl. 22. 1859.
Dicranodontium aristaium Schimp. Syn. 695. 1860. Dicranum virginicum Aust. Bot. Gaz. 4: 150. 1879. Campylopus virginicus Lesq. & James, Man. 80. 1884.
Dioicous: male flowers in separate tufts, terminal, thick, bud-like; inner perigonial leaves abruptly short-pointed with the costa faint or wanting (fide Limpricht) : fertile plants in compact rather dark-green tufts, with stems 3-10 cm. high: leaves often readily deciduous, more or less falcate-secund or sometimes erect-spreading, 5-7 mm. long, from a broadly ovate base rather abruptly narrowed to a rough setaceous point five or six times as long, the leafmargin finely serrulate to and well down the enlarged base; costa one third the width of the* leaf -base, long-excurrent, in cross-section near the base showing stereid-bands above and below the guide-cells with the outer cells differentiated on the dorsal side only, in the upper part of the leaf with cells differentiated on both ventral and dorsal sides; alar cells mostly hyaline, not auriculate, reaching to the costa ; cells in the lower part of the blade oblong, pale, thinwalled, toward the costa up to 20 n wide and 20-30 p long, toward the margin gradually narrower and smaller but scarcely forming a distinct border; inner perichaetial leaves rather longer than the outer, with a convolute base extending one third up and abruptly narrowed to a very rough, often sinuous point: seta about 15 cm. long, mostly erect, straight, strongly twisted when dry, erect-sinuous or slightly curved when moist: capsule oblong, about 1.75 mm. long, without annulus or stomata, the lid with a rostrate beak a little shorter than the capsule; peristometeeth separate to below the mouth, about 200 p high by 40 fi wide at base, divided three fourths down into two rather stout forks, the articulations rather distant, mostly vertically striate on the outer face two thirds up, papillose above: calyptra entire at the base: spores minutely roughened, up to 13 /x in diameter.
Type locality: Sikkim.
Distribution: Virginia to Georgia; Baranoff Islands, Alaska; also in Europe and Asia,

Zwiesiniec szorstki (Dicranodontium asperulum) – gatunek mchu należący do rodziny widłozębowatych (Dicranaceae).

Dicranodontium asperulum là một loài Rêu trong họ Dicranaceae. Loài này được (Mitt.) Broth. mô tả khoa học đầu tiên năm 1901.

粗葉青毛蘚（学名：Dicranodontium asperulum）为曲尾蘚科青毛蘚屬下的一个种。