Sphagnum balticum |
Sphagnum arcticum |
|
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Baltic peat-moss, Baltic sphagnum |
arctic sphagnum |
|
Habit | Plants small to moderate-sized, soft and ± weak-stemmed; brownish green, yellow-green, yellowish to golden brown, capitulum typically flat and 5-radiate. | 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 0.8–1.1 mm, triangular-lingulate to lingulate, concave, spreading, apex broadly obtuse, hyaline cells fibrillose in apical region. |
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 | slender and tapering, often 5-ranked and decurved, leaves somewhat elongated at distal end. |
unranked, terete. |
Branch leaves | ovate-lanceolate, 1–1.7 mm, straight, slightly undulate and spreading; margin entire, hyaline cells on convex surface with 1–5 pores in cell ends and free near apex, on concave surface with round wall thinnings in cell ends and angles; chlorophyllous cells triangular in transverse section and well-enclosed on concave 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 | dioicous. |
unknown. |
Spores | 25–33 µm; smooth to finely papillose on both surfaces; proximal laesura approximately 0.5 spore radius. |
not seen. |
Branch | fascicles with 2 spreading and mostly 1 pendent branch.; branch stem green, cortex enlarged with conspicuous retort cells. |
fascicles with 2 spreading and 1 pendent branch. |
Sphagnum balticum |
Sphagnum arcticum |
|
Habitat | Abundant in hollows and floating mats in raised bogs and poor fens | Forming low hummocks in weakly to moderately minerotrophic fens |
Elevation | low to high elevations | low to moderate elevations |
Distribution |
AK; CO; AB; BC; MB; NT; NU; ON; QC; YT; Greenland; Eurasia |
AK; QC; YT; Eurasia |
Discussion | Unlike Sphagnum angustifolium and S. annulatum, S. balticum has stem leaves exerted at right angles to the stem. It also has fewer and weaker hanging branches than does S. angustifolium, which make the stem itself often visible and the stem leaves easier to see. Sphagnum balticum also lacks the paired pendent branch buds between the capitulum rays as seen in S. angustifolium. In Sphagnum kenaiense there are sometimes spreading stem leaves but this species has 2 hanging branches per fascicle. (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. 65. | FNA vol. 27, p. 89. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | S. recurvum subsp. balticum | |
Name authority | (Russow) C. E. O. Jensen: in Botaniske Forening København, Festskrift, 100. (1890) | K. I. Flatberg & Frisvoll: Bryologist 87: 143, figs. 1–22. (1984) |
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