中位泥炭苔

As the only boreal species of the section with a reddish purple color, Sphagnum magellanicum is usually easy to identify. The branch leaf chlorophyll cells are capable of being confused only with those of S. alaskense, which are less enclosed on both surfaces, and S. centrale, which has thickened end walls on the chlorophyll cells that give them a narrow exposure on the concave surface.

Plants rather robust, stout, pale yellowish green to yellowish brown, young branch tips often tinged with purple, in loose or compact tufts. Stem cortex in 3–5 layers, hyaline cells large, fibrillose, each with 1–4 large, rounded pores; central cylinder pinkish or reddish brown. Stem leaves 1.0–2.0 mm × 0.7–0.8 mm, lingulate, broadened at the apex, borders hyaline and differentiated, often involute; hyaline cells undivided, densely fibrillose, with many pores at the opposite ends in the upper half of the leaves, in the lower half fibrils indistinct, with large, central pores. Branches in fascicles of 4–5, with 2–3 spreading, hyaline cells with fibrils and pores. Branch leaves 1.4–2.0 mm × 1.1–1.3 mm, rounded ovate, imbricate, deeply cucullate-concave, dorsally roughened and rounded at the apex; hyaline cells with large, rounded pores on the ventral surface, mostly with ringed pores at the opposite ends on the dorsal surface; green cells in cross section elliptic, centrally located, entirely enclosed by large, hyaline cells on both surfaces. Dioicous; antheridial branches purple red; perigonial leaves large, broadly ovate. Spores pinkish, densely papillose, 24–28 µm in diameter.

Plants moderate-sized to robust, somewhat lax in shade forms to quite compact and stiff in open grown forms; green to pinkish green to reddish purple; forms lawns in shaded habitats and low to moderately tall, dense hummocks in open habitats. Stems green to purplish red, superficial cortical cells with spiral reinforcing fibrils clearly visible, usually 1 or 2 pores per cell, comb-fibrils lacking on interior wall. Stem leaves to 2 × 0.7 mm; rarely hemiisophyllous; hyaline cells non-ornamented, mostly nonseptate. Branches long and tapering to short and pointed, leaves loosely imbricate. Branch fascicles with 2-3 spreading and 2-3 pendent branches. Branch stems with hyaline cells non-ornamented; no or weak funnel-like projections on the interior end walls, large round pores on superficial cell walls. Branch leaves broadly ovate, to 2 × 1 mm or more wide, broadly ovate, hyaline cells non-ornamented, convex surface with round to elliptic pores along the commissures; chlorophyllous cells short-elliptic in transverse section and well-enclosed on both surfaces. Sexual condition dioicous. Capsule with numerous pseudostomata. Spores 22-30 µm; roughly papillose to nearly smooth, with distinct Y-mark sculpture on distal surface; proximal laesura 0.5-0.8 spore radius.

Distribution: China, Himalayas, India, Indonesia, Russia (Siberia), Europe, North, Central, and South America, and Africa.

Habitat: in peatland or on wet ground under coniferous forests, or on wet soil under Rhododendron brush.

Sphagnum medium Limpr., Bot. Centralbl. 7: 313. 1881.