Sphagnum pylaesii Bridel 1827

Sporophytes rare in Sphagnum pylaesii. This species is distributed as a pioneer on wet rocks associated with S. tenellum and S. papillosum, or in poor fens with S. pulchrum, S. majus, and S. papillosum. See also discussion under 53. S. cyclophyllum.

Plants slender and delicate, aquatic or prostrate, with a conspicuous terminal bud; dark greenish to purplish brown in submerged plants to deep salmon-red in prostrate plants, capitulum quite indistinct but with distinct terminal bud. Stems pale green to brown; superficial cortex of 1-2 layers of thin-walled enlarged cells. Stem leaves broadly ovate, 1.5-2(2.5) mm; straight; hyaline cells fibrillose and nearly aporose, with single small pores occasionally found in the distal cell ends on the concave surface. Branches lacking or short and slender. Branch fascicles none or 1 spreading branch. Branch leaves when present similar to stem leaves but smaller, 0.8-1.2 mm, hyaline cells fibrillose and mostly aporose, 1-6 irregularly round-shaped membrane gaps in some cells near apex on convex surface. Sexual condition dioicous. Capsule usually immersed in perichaetiale leaves, but may be slightly emergent, pseudostomata absent from capsule surface. Spores 29-41 µm, coarsely papillose on both surfaces, indistinct raised sculpture on distal surface; proximal laesura less than 0.5 spore radius.

Hemitheca pylaiei Bridel; Sphagnum pylaesii var. austinii (Husnot) Warnstorf; S. pylaesii var. prostratum (Bridel) Cardot; S. pylaesii var. ramosum Warnstorf; S. sedoides Bridel; S. sedoides var. austinii Husnot; S. sedoides var. prostratum Bridel

Sphagnum pylaesii Brid. Bryol. Univ. 1 : 749. 1827
Sphagnum sedoides Brid. Bryol. Univ. 1: 750. 1827.
Plants sirall and delicate, occasionally very elongate, greenish or nearly always strongly tinged with purple or brown, often nearly black. Wood-cylinder yellowish-green to more or less brownish; cortical cells of the stem well differentiated, in 1-2 layers, the walls of medium thickness, the outer cells narrowly quadrilateral, without fibrils or pores: stem-leaves large, isophyllous, ovate to obovate, concave, rounded at the apex and often somewhat erodedlacerate, the border of 2-3 rows of narrow cells; hyaline cells narrowly rhomboidal throughout, fibrillose, the pores as in branch-leaves: branches none, single, or in fascicles of 2 or 3, in the last case one or two stronger and spreading, their cortical cells in a single layer, the retort-cells but slightly difTerentiated, with inconspicuous necks: branch-leaves imbricate when dry, sometimes slightly subsecund, much smaller than the stem-leaves, broadly ovate, sometimes as wide as or wider than long, strongly concave, with a rounded apex, the border elusive, of 1-2 rows of narrow cells, sometimes hyaline by resorption of the membrane on the inner surface, not however toothed; hyaline cells fibrillose, linear-rhomboidal, 8-10 times as long as wide at the base, much shorter above to 3-4 times in the apex, on the inner surface with pores in the ends of the cells and in the apical part also in the side-comers, here then up to 4 per cell, on the cuter surface with irregular gaps in the apical part of the leaf, passing into longitudinal membrane-pleats below, or with occasional pores in the ends of the cells: chlorophyl-cells nearly rectangular in section, exposed equally on either surface, or trapezoidal with shghtly broader exposure on the inner surface, the lumen broader toward the inner surface ; hyaline cells with very slight convexity on the outer surface, not more than one eighth of the diameter of the cell.
Dioicous. Antheridia in terminal catkins on spreading branches; antheridial leaves hardly differentiated from the normal branch-leaves. Fruiting branches horizontal, hardly differentiated from the normal branches; perichaetial leaves somewhat larger, not sheathing the slender pseudopodium, the uppermost lanceolate-ovate with a blunt toothed apex, with both kinds of cells throughout, the hyaline ones everywhere fibrillose: capsule very small, slightly exserted on a slender pseudopodium, when deoperculate shallowly hemispheric, thinwalled, without pseudostomata : spores yellow, 30-40 ;u' in diameter, very strongly granularroughened.
Type locality: Newfoundland.
Distribution: Labrador to South Carolina; also in France.

Sphaigne de la Pylaie

Sphagnum pylaesii, la sphaigne de la Pylaie est une mousse de couleur rougeâtre se développant en milieu humide de manière permanente.

Sphagnum pylaesii là một loài rêu trong họ Sphagnaceae. Loài này được Brid. mô tả khoa học đầu tiên năm 1827.