Sphagnum acutifolium Schrad. var. plumosum Mild., Bryol. Siles. 382. 1869. Sphagnum plumulosum Röll, Flora 69: 89. 1886, nom. inval. (as Formenreihe).

Plants soft, whitish to grayish green, tinged with reddish brown, shiny when dry, in loose tufts. Stem cortex in 3–4 layers, hyaline cells without fibrils and pores or occasional with a single pore; central cylinder pale green or pale reddish purple. Stem leaves 1.3–1.5 mm × 0.7–0.9 mm, oblong isosceles-triangular, broadly acute, abruptly narrowed to a short, concave-cuspidate point, slightly dentate or lacerate at the apex; borders narrow above, clearly widened near the leaf base; upper hyaline cells rhomboidal, often divided more than once, sometimes divided several times, without fibrils and pores, or rarely with the traces of fibrils. Branches in fascicles of 3–4, with 2 spreading. Branch leaves 1.6–1.8 mm × 0.5–0.6 mm, variable in size, usually ovate-lanceolate, gradually narrowed to a blunt acumen, dentate across the apex; hyaline cells fibrillose, with small pores at the upper ends or lower ends in the upper half, gradually becoming large, rounded pores in the lower half on the ventral surface, with large, half-elliptic pores at the opposite ends along commissural rows on the dorsal surface; green cells in cross section narrowly triangular or trapezoidal, exposed on the ventral surface, enclosed by hyaline cells on the dorsal surface. Dioicous; antheridial branches reddish purple. Perigonial leaves large, ovate, borders wide, hyaline cells without fibrils and pores. Spores yellow, papillose, 25–31 µm in diameter.

Type. Europe.

Chinese specimens examined: GUIZHOU: Ying-jiang Co., J.-X. Jiang 56 (KUN, MO), K.-M. Wang 40018 (KUN). The species was also reported fromYang-bi county, Yunnan province, by Bescherelle (1892).

Habitat: on wet ground and grasslands in high mountain forests; Distribution: China, Himalayas, Russia (Siberia), Europe, North and South America, and North Africa.

This species is similar to Sphagnum junghuhnianum, but it differs in having clearly widened borders near the leaf base, and by having multi-divided hyaline cells of stem leaves without fibrils and pores.

Illustrations: Crum 1984 (Fig. 49, a–l).