Sphagnum isoviitae |
Sphagnum atlanticum |
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Atlantic sphagnum |
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Habit | Plants moderate-sized and moderately weak-stemmed to moderately stiff; green, brownish green to brown; capitulum flat-topped and 5-radiate, terminal bud often visible. | Plants robust and weak-stemmed; green, golden brown to dark brown; capitulum often flat-topped and with a visible terminal bud; flaccid and plumose in submerged forms to more compact in emergent or stranded forms. |
Stem(s) | leaves triangular to lingulate-triangular, equal to or more than 0.8 mm, spreading to appressed; apex acute to apiculate, hyaline cells mostly efibrillose and nonseptate. |
leaves triangular, large, less than 1.7 mm, mostly appressed to stem, apex weakly apiculate to narrowly obtuse; hyaline cells efibrillose and seldom to often septate at base and sides. |
Branches | ± straight and somewhat tapered, usually 5-ranked, leaves not greatly elongated at branch distal end. |
unranked, long and tapering, leaves greatly elongate at distal end. |
Branch leaves | narrowly ovate-lanceolate, greater than 1.2 mm, straight, slightly undulate and weakly recurved when dry, margins entire; hyaline cells on convex surface with 1 pore per cell in apical end, on concave surface with round wall thinnings in the cell ends and angles; chlorophyllous cells in transverse section triangular to ovate-triangular and well-enclosed on the concave surface. |
ovate-lanceolate to lanceolate in aquatic forms, ovate to ovate-lanceolate in emergent forms, greater than 2.5 mm, often falcate-secund, especially in submerged forms, weakly undulate and recurved when dry; margin entire, hyaline cells on convex surface with 0–1 pores per cell, concave surface with round wall thinnings in the cell apices and angles; chlorophyllous cells narrowly triangular in transverse section and well-enclosed on the concave surface. |
Sexual condition | dioicous. |
dioicous. |
Spores | 24–33 µm; finely papillose on the superficial surface. |
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Branch | fascicles with 2 spreading and 2–3 pendent branches.; branch stems green and often reddish at proximal end, with cortex enlarged with conspicuous retort cells. |
fascicles with 2 spreading and 2 pendent branches.; branch stem green, cortex enlarged with conspicuous retort cells. |
Sporophytes | not seen. |
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Sphagnum isoviitae |
Sphagnum atlanticum |
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Habitat | Forming carpets in a wide variety of poor to medium fen habitats of both mire edge and mire wide character, not found in ombrotrophic mires | Forming loose carpets in pools in weakly minerotrophic fens |
Elevation | low to moderate elevations | low elevations |
Distribution |
CT; IN; MA; MD; ME; MI; MN; NC; NH; NJ; NY; OH; PA; VA; VT; WV; AB; NF; NS; QC; Europe |
CT; DE; MA; MD; ME; NC; NH; NJ; NY; PA; RI; VA; VT; NB; NF; NS |
Discussion | Sporophytes are uncommon in Sphagnum isoviitae. See discussion under 26. S. brevifolium and 28. S. fallax for distinction from these similar species. Sphagnum isoviitae has no range overlap with S. pacificum, the other North American species of the S. recurvum complex with apiculate stem leaves; the sharply recurved branch leaves of the latter, however, would separate it easily in any case. Spore features are those given by Flatberg. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Sporophytes of Sphagnum atlanticum are rare. The other large North American Atlantic coastal plain species of sect. Cuspidata, S. torreyanum, is typically more yellow, has a more rounded capitulum, and has straight rather than subsecund branch leaves. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 27, p. 68. | FNA vol. 27, p. 65. |
Parent taxa | ||
Sibling taxa | ||
Name authority | Flatberg: J. Bryol. 17: 2, figs. 1, 2. (1992) | R. E. Andrus: Bryologist 110: 274, figs. (2007) |
Web links |