Sphagnum balticum |
Sphagnum perichaetiale |
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Baltic peat-moss, Baltic sphagnum |
sphagnum |
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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 ± moderate-sized, compact and stiff-stemmed; forming dense to somewhat loose low cushions in often seasonally dry depressions. |
Stem(s) | leaves 0.8–1.1 mm, triangular-lingulate to lingulate, concave, spreading, apex broadly obtuse, hyaline cells fibrillose in apical region. |
leaves to 1.1 × 0.7 mm, commonly hemiisophyllous; hyaline cells non-ornamented, mostly 1–2-septate. |
Branches | slender and tapering, often 5-ranked and decurved, leaves somewhat elongated at distal end. |
short and blunt at distal end, leaves loosely spreading. |
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. |
ovate, to 2.2 × 1.1 mm; ovate, hyaline cells non-ornamented, on proximal half of convex surface with small ringed pores or pseudopores in groups of three where the corners join and pseudopores along the commissures; chlorophyllous cells narrowly rectangular, lenticular to narrowly trapezoidal in transverse section; exposed equally on both surfaces or more broadly on concave surface; end walls not thickened. |
Sexual condition | dioicous. |
dioicous. |
Capsule | with numerous pseudostomata. |
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Spores | 25–33 µm; smooth to finely papillose on both surfaces; proximal laesura approximately 0.5 spore radius. |
25–39 µm; surface smooth to irregularly and finely papillose; indistinct Y-mark on distal surface; proximal laesura more than 0.6 spore radius. |
Branch | fascicles with 2 spreading and mostly 1 pendent branch.; branch stem green, cortex enlarged with conspicuous retort cells. |
fascicles with 2 spreading and 1–2 pendent branches.; branch stems with hyaline cells non-ornamented, no or weak funnel-like projection of end walls of cortical cells, cortical cells with one large pore per cell on superficial wall. |
Sphagnum balticum |
Sphagnum perichaetiale |
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Phenology | Capsules common, mature late spring to early summer. | |
Habitat | Abundant in hollows and floating mats in raised bogs and poor fens | Mostly ruderal, wet depressions in sandy substrates, often in areas recently burned, also low to moderate-sized hummocks in Chamaecyparis swamps |
Elevation | low to high elevations | low to high elevations |
Distribution |
AK; CO; AB; BC; MB; NT; NU; ON; QC; YT; Greenland; Eurasia |
AL; DE; FL; GA; LA; MD; MS; NC; NJ; SC; TX; VA; South America; se Asia; s Africa; Pacific Islands (New Zealand) |
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.) |
The compact growth form in thin but dense mats and occurrence in often dessication-prone sites distinguishes Sphagnum perichaetiale from any other species of sect. Sphagnum. The often quite stiffly spreading branch leaves give it a strong resemblance to S. compactum, but the latter’s small triangular stem leaves will readily distinguish that species. The branch leaf hyaline cells of S. perichaetiale have only a few pores on their convex surface, and they are typically small, thickened, and grouped in 3s where the cell corners meet. Similar species in sect. Sphagnum have more pores along the commissures, and they are more elliptical and not thickened. The often hemiisophyllous stem leaves are also diagnostic of S. perichaetiale within the section. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 27, p. 65. | FNA vol. 27, p. 54. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | S. recurvum subsp. balticum | S. brevicaule, S. cymbifolium var. ludovicianum, S. harperi, S. ludovicianum |
Name authority | (Russow) C. E. O. Jensen: in Botaniske Forening København, Festskrift, 100. (1890) | Hampe: Linnaea 20: 66. (1847) |
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