Sphagnum magellanicum |
Sphagnum obtusum |
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Magellan's sphagnum, magellanic peat-moss |
sphagnum |
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Habit | 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. | Plants moderate to robust, weak-stemmed, yellow, yellowish brown to golden brown; capitulum varying from rounded, not 5-radiate and twisted to flat 5-radiate and straight branched. |
Stem(s) | leaves to 2 × 0.7 mm; rarely hemiisophyllous; hyaline cells non-ornamented, mostly nonseptate. |
pale green to pale brown; superficial cortex of weakly to moderately differentiated.; stem leaves triangular-lingulate, 0.9–1.3 mm; usually appressed; apex obtuse and often erose; hyaline cells efibrillose and nonseptate. |
Branches | long and tapering to short and pointed, leaves loosely imbricate. |
tapering or in more robust forms, frequently blunt, straight to arcuate, leaves slightly to moderately elongated at distal end. |
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. |
ovate to ovate-lanceolate; more than 1.8 mm; straight, stiff, not much undulate and reflexed to recurved; margins entire; hyaline cells on convex surface with a few end pores, but mostly numerous small to very small (often barely visible) pores or wall thinnings free from the commissures, on concave surface similar, but with pores generally fewer and larger; chlorophyllous cells triangular in transverse section, just reaching concave surface or slightly enclosed. |
Sexual condition | dioicous. |
dioicous. |
Capsule | with numerous pseudostomata. |
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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. |
18–27 µm; both surfaces covered with rough, irregular verrucate plates of papillae, bifurcated Y-mark sculpture on distal surface; proximal laesura less than 0.5 spore radius. |
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. |
fascicles with 2 spreading and 2 pendent branches.; branch stems green, with cortex enlarged with conspicuous retort cells. |
Sphagnum magellanicum |
Sphagnum obtusum |
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Phenology | Capsules mature mid summer. | |
Habitat | Ecological amplitude very wide, ombrotrophic to rich fen peatlands, forested and open mires | Forming carpets in minerotrophic peatlands |
Elevation | low to high elevations | low to moderate elevations |
Distribution |
AK; AL; AR; CA; CT; DE; FL; GA; ID; IL; IN; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; NH; NJ; NY; OH; OR; PA; SC; TN; TX; VA; VT; WA; WI; WV; AB; BC; MB; NB; NF; NS; NT; ON; PE; QC; SK; YT; South America; Eurasia
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AK; MN; AB; BC; MB; NF; NT; NU; ON; QC; SK; YT; Greenland; Eurasia |
Discussion | 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. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Sporophytes are uncommon in Sphagnum obtusum. This is a quite phenotypically variable species that warrants further investigation, which may result in taxonomic splitting. The strongly obtuse stem leaf should separate it from any similar species with which it occurs. Sphagnum mendocinum looks similar phenotypically but there appears to be no range overlap with S. obtusum. The tiny branch leaf pores, which may seem like no more than pinpricks in the cell surface, easily separate S. obtusum microscopically from other species of sect. Cuspidata. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 27, p. 52. | FNA vol. 27, p. 73. |
Parent taxa | Sphagnaceae > Sphagnum > sect. Sphagnum | Sphagnaceae > Sphagnum > sect. Cuspidata |
Sibling taxa | ||
Name authority | Bridel: Muscol. Recent. 2(1): 24. (1798) | Warnstorf: Bot. Zeitung (Berlin) 35: 478. (1877) |
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