Dicranoweisia Moss

Dicranoweisia crispula is an extremely variable species. In stature the plants vary 1-6 cm, while the leaf length varies 1-3.5 mm. The capsules vary considerably from cylindric to short-elliptic, with the length ranging 0.5-2 mm. The shape and sheathing of the perichaetial leaves is also variable. Although this species is autoicous, sex organs are often absent, especially in terrestrial plants, with sporophytes correspondingly infrequent. Differentiation of alar cells is often weak in North American material and the striolation can also be weak, and is best observed on cells adjacent to the costa. This species is widespread mainly at higher elevations in western North America, but sporadic in the eastern part of the continent, again occurring mainly at higher elevations.

Plants slender, up to 1.1 cm high, dull, yellowish green or sometimes blackish, in tufts. Stems erect, often branched, radiculose at base. Leaves up to 3.5 mm long, strongly crispate and incurved when dry, erect spreading and flexuose, sometimes secund when moist, oblong-lanceolate and concave at the base, rather gradually narrowed to a long, slender, subtubulose acumen; margins plane, entire, unistratose; costa percurrent to shortly excurrent, with stereid bands in transverse section; upper cells irregularly quadrate, ca. 7–10 µm wide, thick-walled, often appearing papillose because of longitudinal ridges (striae); basal cells elongate, rectangular, 20–35 µm × 8–10 µm, thin- to thick-walled; alar cells well differentiated in a small group, yellowish or brownish. Autoicous. Outer perichaetial leaves rather short-acuminate, the inner ones with a long sheathing and convolute base and a shortly attenuate or obtuse apex. Setae straight, 7–14 mm long, yellowish to brownish; capsules elongate-ovoid to cylindric, sometimes with a short neck, finely wrinkled when dry; opercula oblong-rostrate, ca. 1 mm long; annuli none; peristome teeth brownish, undivided, distinctly papillose on both surfaces, sometimes papillae in vertical or oblique rows at the base, appearing striolate. Spores 12–18 µm in diameter, pale, smooth.

Leaves crisped and curled when dry, plane in many leaves, 2-stratose in distal ¹/2, cells with longitudinal striolae in distal ¹/2 of leaf; usually a few alar cells enlarged on margins, often colored. Specialized asexual reproduction absent. Capsule without differentiated annulus; peristome vertically striolate basally, weakly papillose distally.

Distribution: China, Korea, Japan, Russia, Europe, and North America.

Habitat: on calcareous or siliceous rocks or boulders.

Weissia crispula Hedwig, Sp. Musc. Frond., 68. 1801; Dicranoweisia crispula var. compacta (Schwägrichen) Lindberg; D. contermina Renauld & Cardot; D. roellii Kindberg; Trichostomum alpinum Kindberg; Weissia compacta Schwägrichen

Dicranoweisia crispula (Hedw.) Lindb. Oefv. Sv. Vet.-Akad
Forh. 21 : 230. 1864.
Weisia crispula Hedw. Sp. Muse. 68, 1801.
Weisia convoluta C. Mull. & Kindb.; Macoun, Cat. Can. PI. 6: 14. 1892.
Monoicous: male flower either at the base of the perichaetium or terminating a branch, of about three short-ovate, costate or one half costate, entire leaves enclosing numerous antheridia and paraphyses: plants in compact, yellowish-green or sometimes blackish cushions, 1-2 cm., rarely up to 4 cm. high: stem-leaves spreading on all sides, crispate when dry, up to about 4 mm. long, from a narrowly ovate or oblong base gradually narrowed to a grooved, entire point, somewhat rough on the back with mamillose cells, the margins somewhat incurved; costa nearly percurrent, mostly 40-55 M wide at the base and one third to one fifth the width of the leaf-base; alar 'cells mostly distinct, colored, enlarged, short-quadratic; lower leaf-cells rectangular or linear, with thickened walls, toward the costa usually 6-12 times as long as wide, toward the margin shorter and broader, the upper ones short, oblong to slightly transversely elongate, about 6 n by 5-8 n outer perichaetial leaves with a broadish base rather abruptlynarrowed to the flexuous point, the inner convolute to a truncate or rounded apex: seta erect, 8-15 mm. long: capsule erect, symmetric, oval-cylindric, mostly pale-brown, somewhat rugose when dry, up to 2.5 mm. long; annulus wanting; lid with a slender beak one half as long as the capsule or longer; peristometeeth when dry often incurved and scarcely visible above the mouth, rather coarsely papillose, at the apex entire or somewhat divided, without a distinct median line and with 8-12 articulations: spores smooth or nearly so, about 13 fi in diameter.
Type locality: Austria.
Distribution: Alaska to California and eastward to Wyoming and Montana; Greenland; Labrador ; Mt. Marcy, New York ; also in Europe, Asia, and Africa.

Dicranoweisia crispula, the mountain pincushion, is a species of mosses that lives at both poles. It grows in the South Shetland Islands and on the Antarctic Peninsula.