Sphagnum austinii |
Sphagnum arcticum |
|
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Austin's peat-moss, Austin's sphagnum |
arctic sphagnum |
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Habit | Plants moderate-sized to large, usually quite compact; reddish brown and often yellow flecked with red-brown; in dense stands forming large and tall hummocks. | 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 1.2–1.6 × 1 mm; rarely hemiisophyllous; hyaline cells nonseptate or more typically mostly septate, comb-lamellae present on interior wall. |
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 | clavate, tapering to short point, tightly imbricate at proximal end to somewhat spreading at distal end in less compact forms. |
unranked, terete. |
Branch leaves | ovate-elliptical to elliptical, 1.5–2.1 × 0.8–1.4 mm; hyaline cells on convex surface with numerous moderate-sized round pores along the commissures, comb-lamellae present throughout most of leaf; chlorophyllous cells broadly triangular in transverse section and well-enclosed on the convex surface, end wall not thickened. |
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 | dioicous. |
unknown. |
Capsule | with scattered pseudostomata. |
|
Spores | 23–28 µm; coarsely granulate on both surfaces; proximal laesura more than 0.50 spore radius. |
not seen. |
Branch | fascicles with 2 spreading and 1 pendent branch.; branch stems with cortical cell comb-lamellae visible on interior wall, conspicuous funnel-like projection on interior end walls extending to next cell less than one half its length, pores in superficial wall restricted to leaf bases. |
fascicles with 2 spreading and 1 pendent branch. |
Sphagnum austinii |
Sphagnum arcticum |
|
Phenology | Capsules common, mature mid summer. | |
Habitat | Ombrotrophic mires and large hummocks in blanket mires | Forming low hummocks in weakly to moderately minerotrophic fens |
Elevation | low to moderate elevations | low to moderate elevations |
Distribution |
AK; MA; ME; NJ; VT; WA; BC; NB; NF; NS; Europe |
AK; QC; YT; Eurasia |
Discussion | Sphagnum austinii is usually easily recognized in the field by its strongly imbricate and clavate branches. It forms very dense and often tall hummocks with a distinct deep golden brown color. In contrast to the view stated by H. A. Crum (1997), this species has an ecology and distribution quite distinct from those of S. affine. Sphagnum affine is a minerotrophic species that does not even occur in the Pacific coast region, where S. austinii is quite prominent. (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. 50. | FNA vol. 27, p. 89. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | S. cymbifolium subsp. austinii, S. cymbifolium var. austinii, S. imbricatum subsp. austinii | |
Name authority | Sullivant: in C. F. Austin, Musci Appalach., 2. 1870 (as austini), | K. I. Flatberg & Frisvoll: Bryologist 87: 143, figs. 1–22. (1984) |
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