Sphagnum jensenii |
Sphagnum tenerum |
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jensen's sphagnum |
sphagnum |
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Habit | Plants moderate-sized to robust, weak-stemmed; pale brown to chestnut brown; capitulum flat-topped and generally 5-radiate, branches straight to somewhat curved, terminal bud often visible. | 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 triangular, ovate-triangular to triangular-lingulate, 1–1.3 mm; appressed to spreading; apex obtuse, hyaline cells usually fibrillose near apex. |
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 | straight to somewhat curved, leaves moderately elongate at distal end. |
turgid and terete, leaves, not 5-ranked. |
Branch leaves | ovate-lanceolate; usually more than 2 mm; straight; weakly undulate and slightly recurved when dry, margins entire; hyaline cells on convex surface with numerous small free pores in proximal 2/3 of leaf and in apical region with numerous pseudopores along commissures, on concave surface with numerous round free pores; cells relatively long and narrow in basal region, much longer than in mid region; chlorophyllous cells triangular in transverse section and well-enclosed on concave 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. |
Spores | 29–33 µm; both surfaces very smooth; proximal laesura long, more than 0.6 spore radius. |
22–25 µm, finely roughened. |
Branch | fascicles with 2 spreading and 1–2 pendent branches.; branch stems green, cortex enlarged with conspicuous retort cells. |
fascicles with 2 spreading and 1–2 pendent branches. |
Sphagnum jensenii |
Sphagnum tenerum |
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Habitat | Predominantly in wet carpets in poor to medium fen habitats, mostly in mire-wide vegetation | Damp sand and thin humus especially around pond margins, open savannas, and pine barrens |
Elevation | low to moderate elevations | low to moderate elevations |
Distribution |
AK; AB; BC; NF; NT; ON; QC; SK; YT; Eurasia |
AL; DC; DE; FL; GA; KY; MD; NC; NJ; NY; PA; RI; SC; TN; VA |
Discussion | Sporophytes of Sphagnum jensenii are uncommon. For more information, see discussion under 23. S. annulatum. (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. 69. | FNA vol. 27, p. 100. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | S. annulatum var. porosum | S. capillaceum var. tenerum, S. capillifolium var. tenerum, S. tenerum var. virginicum |
Name authority | H. Lindberg: Acta Soc. Fauna Fl. Fenn. 18(3): 13. (1899) | Sullivant: in A. Gray, Manual ed. 2, 611. (1856) |
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