24. Sphagnum obtusiusculum Lindb. ex Warnst., Hedwigia. 29: 196. 1890.
Plants medium- to large-sized, generally slender, to 12 cm high, grayish, tinged with pink when wet, yellowish when dry, in loose tufts. Stem cortex in 2–3 layers, hyaline cells large, thin-walled, without fibrils; central cylinder yellowish or pale pinkish. Stem leaves 1.1–1.4 mm × 0.6–0.7 mm, short ligulate, slightly narrowed and rounded, irregularly dentate at the apex; borders narrow above, somewhat widened below; hyaline cells rhomboidal, mostly divided, without fibrils, or rarely with fibrils and pores in the upper leaf. Branches in fascicles of 4, with 2 spreading and 2 pendent, slender. Branch leaves 1.0–1.5 mm × 0.4–0.5 mm, imbricate, erect at the tips, oblong-ovate to lanceolate with rather narrowed acumen, margins involute in the upper half; hyaline cells narrowly rhomboidal, irregularly fibrillose and with half-elliptic pores at the opposite ends on the dorsal surface, with numerous large, central pores on the ventral surface; green cells in cross section triangular or trapezoidal, exposed more broadly on the ventral surface, slightly exposed or enclosed by hyaline cells on the dorsal surface. Dioicous. Sporophytes not seen.
Type. South Africa.
Chinese specimens examined: HEILONGJIANG: C. Gao 838 (IFSBH, KUN, MO). JIANGXI: Lu Shan (Mt.), P.-C. Chen et al. 52 (KUN). SICHUAN: Emei Shan (Mt.), Sichuan Univ. Biol. 10002 (PE). XIJIANG: Buer-jin Co., S.-L. Chen 387 (KUN, MO), Q.-T. Wang 384 (KUN). YUNNAN: between Nu-jiang (river) and Lan-cang-jiang (river), Handel-Mazzetti 8372 (H); Gaoligong Shan (Mt.), X.-Z. Qiu 2(e) (KUN); Gong-shan Co., Q.-W. Wang 6727, 33723 (KUN, PE), M. Zang 529, 2905 (KUN), D.-C. Zhang 461 (KUN, MO).
Habitat: in bogs or on wet ground under coniferous forests in high mountains; Distribution: China, South Africa, and Madagascar.
This species is similar to Sphagnum acutifolioides, but it differs in having shorter stem leaves with rounded apices and broader borders at base, and in having oblong-ovate or lanceolate branch leaves with gradually narrowed apices. In contrast, Sphagnum acutifolioides has longer stem leaves with obtuse apices and narrower borders at base, and has broadly ovate branch leaves with abruptly narrowed apices.
Illustrations: C. Gao (ed.) 1994 (Pl. 11, figs. 1–10).