Sphagnum angustifolium |
Sphagnum obtusum |
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fine bogmoss, poor-fen peat-moss, sphagnum |
sphagnum |
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Habit | Plants small and often slender and soft, lax to compact, moderately stiff-stemmed; green to pale yellow to golden brown to brown; capitulum strongly convex in drier grown forms to strongly 5-radiate and flat in wetter growing forms. | 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 equilateral to isosceles-triangular, small, less than 0.8 mm, mostly appressed to stem, apex acute to obtuse, hyaline cells efibrillose and 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 | straight to slightly curved, usually 5-ranked; leaves not much longer at distal end than proximal end. |
tapering or in more robust forms, frequently blunt, straight to arcuate, leaves slightly to moderately elongated at distal end. |
Branch leaves | narrowly ovate-lanceolate, 0.8–1 mm, straight, moderately undulate and recurved in larger and/or wetter grown forms, not undulate and slightly recurved in compact forms from drier sites; margins entire; hyaline cells on convex surface with 1(2–3) pore per cell at apical end of cell, on concave surface with round wall thinnings in cell ends and angles; chlorophyllous cells triangular in transverse section and just enclosed on concave surface. |
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. |
Spores | 21–25 µm; coarsely papillose on proximal and distal surfaces; proximal laesura more than 0.5 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 spreading and 2–3 pendent branches.; branch stems with cortex enlarged with conspicuous retort cells, often pinkish red at proximal end. |
fascicles with 2 spreading and 2 pendent branches.; branch stems green, with cortex enlarged with conspicuous retort cells. |
Sphagnum angustifolium |
Sphagnum obtusum |
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Habitat | Wide range of habitats, from ombrotrophic to rich fens, open mires, sedge fens and muskeg, as carpets, floating mats, low hummocks and hummock sides | Forming carpets in minerotrophic peatlands |
Elevation | low to high elevations | low to moderate elevations |
Distribution |
AK; CA; CO; ID; IL; IN; MA; MD; ME; MI; MN; MO; MT; NC; ND; NH; NJ; NY; OH; OR; PA; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NB; NF; NS; NT; ON; QC; SK; YT; Greenland; Eurasia
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AK; MN; AB; BC; MB; NF; NT; NU; ON; QC; SK; YT; Greenland; Eurasia |
Discussion | The sporophytes of Sphagnum angustifolium are somewhat common. This species is distinguished from similar ones in sect. Cuspidata by the small, triangular, obtuse and appressed stem leaves. It also often has a pink stem, as opposed to the reddish branch bases seen in some other species of the section. Sphagnum balticum has stem leaves that are more lingulate-triangular as well as spreading from the stem. Sphagnum angustifolium belongs to a subgroup within sect. Cuspidata usually referred to as S. recurvum, in the broad sense, a group of mostly carpet-forming species that differ from other members of the section in having pairs of pendent branch buds visible between the capitulum rays. The group also includes S. brevifolium, S. fallax, S. flexuosum, S. pacificum, S. recurvum, S. rubroflexuosum, and S. splendens. (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. 64. | FNA vol. 27, p. 73. |
Parent taxa | Sphagnaceae > Sphagnum > sect. Cuspidata | Sphagnaceae > Sphagnum > sect. Cuspidata |
Sibling taxa | ||
Synonyms | S. recurvum var. angustifolium, S. amblyphyllum var. parvifolium, S. flexuosum var. tenue, S. parvifolium, S. recurvum var. parvifolium, S. recurvum var. tenue | |
Name authority | (Warnstorf) C. E. O. Jensen: Bih. Svenska Vetensk.-Akad. Handl. 16(9): 46. (1891) | Warnstorf: Bot. Zeitung (Berlin) 35: 478. (1877) |
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