Sphagnum trinitense |
Sphagnum arcticum |
|
---|---|---|
Trinity sphagnum |
arctic sphagnum |
|
Habit | 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. | Plants moderately robust, capitulum distinct and flat-topped; golden brown, brown or dark-brown, less commonly variegated green and brown, without metallic luster when dry. |
Stem(s) | 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. |
leaves narrowly to broadly lingulate or sometimes lingulate-spatulate, (1.1–)1.2–1.4(–1.6) mm; apex broadly obtuse to obtuse-truncate and more or less fimbriate-lacerately resorbed, border in distal half narrow and often indistinct, in proximal half widened and filling up 1/3–1/2(–2/3) of the breadth at the base; hyaline cells broadly S-shaped to rhombic S-shaped, predominantly nonseptate but a few cells are 1–3-septate; efibrillose. |
Branches | straight and unranked, in capitulum tapering at distal end to a point, leaves greatly elongated at distal end. |
unranked, terete. |
Branch leaves | 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. |
broadly lanceolate to ovate-lanceolate, (1.1–)1.4–1.8(–2.1) mm, slightly concave, straight to slightly subsecund; apex involute; border entire; hyaline cells on convex surface with (5–)8–10(–12) semicircular to elliptical, ringed pores along the commissures, concave surface aporose or infrequently with 1–2 pores per cell in the distal portion of the cell, more numerous along leaf margins. |
Sexual condition | monoicous. |
unknown. |
Spores | 26–40 µm; ± roughly to densely granulose. |
not seen. |
Branch | stems green, cortex enlarged with conspicuous retort cells. |
fascicles with 2 spreading and 1 pendent branch. |
Sphagnum trinitense |
Sphagnum arcticum |
|
Phenology | Capsules mature early to mid summer. | |
Habitat | Submersed or stranded at edge of shallow, acidic pond, lakes, and roadside ditches, mostly in sandy areas of the Atlantic coastal plain | Forming low hummocks in weakly to moderately minerotrophic fens |
Elevation | low to moderate elevations | low to moderate elevations |
Distribution |
DE; FL; GA; IL; KS; LA; MA; MD; NC; NJ; NY; PA; SC; VA; South America |
AK; QC; YT; Eurasia |
Discussion | 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.) |
Sporophytes are uncommon in Sphagnum arcticum. All collections of this fairly common species have been made north of 59° N latitude in wet or moist tundra vegetation. In its typical dark brown color, this species is often quite distinctive in the field. Sphagnum fuscum is smaller, not as dark, and its stem leaves are not as truncate-lacerate. Sphagnum subfulvum has a glossy sheen, which S. arcticum lacks, and its stem leaf has an obtuse but not lacerate apex. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 27, p. 77. | FNA vol. 27, p. 89. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | S. cuspidatum var. serratum, S. cuspidatum var. serrulatum, S. helleri, S. laxifolium var. serrulatum, S. serratum | |
Name authority | Müller Hal.: Syn. Musc. Frond. 1: 102. (1848) | K. I. Flatberg & Frisvoll: Bryologist 87: 143, figs. 1–22. (1984) |
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