Sphagnum atlanticum |
Sphagnum trinitense |
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Atlantic sphagnum |
Trinity sphagnum |
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Habit | 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. | Plants moderate-sized, slender and weak-stemmed, green to pale yellow; flaccid and plumose in aquatic forms to more compact and sprawling in emergent forms; green to pale yellow; capitulum not especially enlarged and differentiated. |
Stem(s) | 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. |
leaves ovate-triangular to triangular, 1–1.6 mm; appressed to spreading; apex acute to slightly obtuse; hyaline cells often fibrillose and often 1-septate. |
Branches | unranked, long and tapering, leaves greatly elongate at distal end. |
straight and unranked, in capitulum tapering at distal end to a point, leaves greatly elongated at distal end. |
Branch leaves | 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. |
ovate-lanceolate to lanceolate, 2–3.5 mm; straight, undulate and slightly recurved when dry; margin serrulate; hyaline cells on convex surface with 0–1 small pores at cell apex on concave surface with round wall thinnings in cell angles (often indistinct or lacking); chlorophyllous cells trapezoidal in transverse section and exposed more broadly on the convex surface. |
Sexual condition | dioicous. |
monoicous. |
Spores | 26–40 µm; ± roughly to densely granulose. |
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Branch | fascicles with 2 spreading and 2 pendent branches.; branch stem green, cortex enlarged with conspicuous retort cells. |
stems green, cortex enlarged with conspicuous retort cells. |
Sporophytes | not seen. |
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Sphagnum atlanticum |
Sphagnum trinitense |
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Phenology | Capsules mature early to mid summer. | |
Habitat | Forming loose carpets in pools in weakly minerotrophic fens | Submersed or stranded at edge of shallow, acidic pond, lakes, and roadside ditches, mostly in sandy areas of the Atlantic coastal plain |
Elevation | low elevations | low to moderate elevations |
Distribution |
CT; DE; MA; MD; ME; NC; NH; NJ; NY; PA; RI; VA; VT; NB; NF; NS |
DE; FL; GA; IL; KS; LA; MA; MD; NC; NJ; NY; PA; SC; VA; South America |
Discussion | 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.) |
Sporophytes are common in Sphagnum trinitense, which can often be distinguished from S. cuspidatum in the field by the appearance of its branches when wet. In this state the branches of S. trinitense just below the capitulum resemble a fine paintbrush drawn out to a pointed tip. See also discussion under 29. S. fitzgeraldii and 39. S. mississippiense. Spore features are taken from H. A. Crum (1984). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 27, p. 65. | FNA vol. 27, p. 77. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | S. cuspidatum var. serratum, S. cuspidatum var. serrulatum, S. helleri, S. laxifolium var. serrulatum, S. serratum | |
Name authority | R. E. Andrus: Bryologist 110: 274, figs. (2007) | Müller Hal.: Syn. Musc. Frond. 1: 102. (1848) |
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