Sphagnum recurvum |
Sphagnum perichaetiale |
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recurved sphagnum |
sphagnum |
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Habit | Plants moderate-sized to robust, moderately stiff-stemmed, ± lax, but not compact; green to pale yellow to yellowish brown; capitulum typically strongly convex in open grown forms, but flat and ± 5-radiate in shade forms. | Plants ± moderate-sized, compact and stiff-stemmed; forming dense to somewhat loose low cushions in often seasonally dry depressions. |
Stem(s) | pale green to yellowish; superficial cortex of 2 layers of enlarged, thin-walled and well differentiated cells.; stem leaves triangular, triangular-lingulate to lingulate, more than 0.8 mm, appressed, apex obtuse to broadly obtuse, erose to fimbriate; hyaline cells efibrillose and nonseptate. |
leaves to 1.1 × 0.7 mm, commonly hemiisophyllous; hyaline cells non-ornamented, mostly 1–2-septate. |
Branches | straight and often tapering, often 5-ranked, leaves not much elongate at distal end of branches. |
short and blunt at distal end, leaves loosely spreading. |
Branch leaves | ovate-lanceolate, 1.4–2 mm, straight; slightly undulate and sharply recurved; margins entire; hyaline cells on convex surface with 1 pore per cell at cell apex, concave surface with round wall thinnings in the 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 | 22–28 µm; papillose on both surfaces; proximal laesura more than 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 2 pendent branches.; branch stems 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 recurvum |
Sphagnum perichaetiale |
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Phenology | Capsules mature late summer to early fall. | Capsules common, mature late spring to early summer. |
Habitat | Forming carpets in a variety of very poor to poor fen habitats, including sedge fens, pocosins, bay swamps | Mostly ruderal, wet depressions in sandy substrates, often in areas recently burned, also low to moderate-sized hummocks in Chamaecyparis swamps |
Elevation | low to moderate elevations | low to high elevations |
Distribution |
AL; AR; CT; DE; FL; GA; IL; IN; KY; LA; MA; MD; ME; MO; MS; NC; NH; NJ; NY; OH; PA; SC; TN; TX; VA; VT; WV; NF; NS; South America
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AL; DE; FL; GA; LA; MD; MS; NC; NJ; SC; TX; VA; South America; se Asia; s Africa; Pacific Islands (New Zealand) |
Discussion | Sporophytes in Sphagnum recurvum are uncommon. This species is found exclusively in the New World. It has several strong characters that distinguish it from S. flexuosum, and the opinion of H. A. Crum (1997) that the two species are synonymous is rejected. See discussion under 30. S. flexuosum. (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. 75. | FNA vol. 27, p. 54. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | S. pentastichon, S. pulchricoma, S. riparioides | S. brevicaule, S. cymbifolium var. ludovicianum, S. harperi, S. ludovicianum |
Name authority | P. Beauvois: Prodr. Aethéogam., 88. (1805) | Hampe: Linnaea 20: 66. (1847) |
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