Sphagnum pylaesii |
Sphagnum tenerum |
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Pylaes' sphagnum |
sphagnum |
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Habit | 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. | Plants ± robust, weak-stemmed, and compact, capitulum hemispherical, branches in capitulum short and blunt; typically mottled pale yellow-green and purplish red, without metallic sheen when dry. |
Stem(s) | 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. |
leaves 1.4–1.8 mm, elongate-triangular, lingulate-triangular, hemiisophyllous forms elongate triangular-ovate, 1.4–1.8 mm, apex usually conspicuously toothed, border narrow at base (less than 0.25 width); hyaline cells narrowly rhombic to S-shaped, can be efibrillose and aporose but more commonly fibrillose and porose, 0–1-septate. |
Branches | lacking or short and slender. |
turgid and terete, leaves, not 5-ranked. |
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. |
ovate, 1.1–1.7 mm, slightly concave, straight, apex weakly involute and conspicuously toothed; hyaline cells on the convex surface with round to elliptic pores along the commissures, grading from moderate-sized pores near apex to large pores at leaf base, concave surface with large round pores throughout. |
Sexual condition | dioicous. |
uncertain, monoicous or dioicous or possibly both. |
Capsule | usually immersed in perichaetiale leaves, but may be slightly emergent, pseudostomata absent from capsule surface. |
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Spores | 29–41 µm, coarsely papillose on both surfaces, indistinct raised sculpture on distal surface; proximal laesura less than 0.5 spore radius. |
22–25 µm, finely roughened. |
Branch | fascicles none or 1 spreading branch. |
fascicles with 2 spreading and 1–2 pendent branches. |
Sphagnum pylaesii |
Sphagnum tenerum |
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Habitat | Weakly minerotrophic, wet rocks, poor fens | Damp sand and thin humus especially around pond margins, open savannas, and pine barrens |
Elevation | low to high elevations | low to moderate elevations |
Distribution |
MA; ME; NC; NH; NJ; NF; NS; QC; Greenland; NY ; Europe
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AL; DC; DE; FL; GA; KY; MD; NC; NJ; NY; PA; RI; SC; TN; VA |
Discussion | 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. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Sporophytes are uncommon in Spagnum tenerum. The sexual condition is uncertain because of past taxonomic confusion with S. capillifolium (R. E. Andrus 1980). Sphagnum tenerum is usually described (incorrectly) as having hemiisophyllous stem leaves, and many collections of other species of sect. Acutifolia with such leaves have been called S. tenerum. When correctly characterized, S. tenerum is can be confused only with S. capillifolium, with which it has only a very small range overlap. Microscopically, besides the otherwise quite different S. angermanicum, S. tenerum is the only species of sect. Acutifolia with large round free pores in most of the branch leaf hyaline cells on their concave surfaces. See also discussion under 71. S. capillifolium. Sexual condition and spore features were taken from H. A. Crum (1984). The name Sphagnum evansii Warnstorf has also been used for this taxon. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 27, p. 84. | FNA vol. 27, p. 100. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Hemitheca pylaiei, S. pylaesii var. austinii, S. pylaesii var. prostratum, S. pylaesii var. ramosum, S. sedoides, S. sedoides var. austinii, S. sedoides var. prostratum | S. capillaceum var. tenerum, S. capillifolium var. tenerum, S. tenerum var. virginicum |
Name authority | Bridel: Bryol. Univ. 1: 749. (1827) | Sullivant: in A. Gray, Manual ed. 2, 611. (1856) |
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