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sphagnum

sphagnum

Habit Plants small to moderate-sized, slender, fairly stiff but soft, capitulum flat-topped and stellate; deep maroon-red to variegated red and yellowish green, lacking metallic sheen when dry. Plants moderate to robust, weak-stemmed, yellow, yellowish brown to golden brown; capitulum varying from rounded, not 5-radiate and twisted to flat 5-radiate and straight branched.
Stem(s)

leaves lingulate-triangular to lingulate, 1–1.4 mm, apex broadly rounded but becoming acute in hemiisophyllous forms, border strongly developed at base (more than 0.25 width);

hyaline cells rhombic and 0–3-septate with some cells in leaf midregion 2–septate.

pale green to pale brown;

superficial cortex of weakly to moderately differentiated.;

stem leaves triangular-lingulate, 0.9–1.3 mm; usually appressed;

apex obtuse and often erose;

hyaline cells efibrillose and nonseptate.

Branches

weakly to strongly 5-ranked.

tapering or in more robust forms, frequently blunt, straight to arcuate, leaves slightly to moderately elongated at distal end.

Branch leaves

ovate to ovate-lanceolate, 0.9–1.2 mm, concave, subsecund on some branches, apex involute;

hyaline cells on convex surface with numerous round to elliptic pores along the commissures, grading from small round pores near apex to round pores near base, on concave surface with large round pores in proximal portions of leaf.

ovate to ovate-lanceolate; more than 1.8 mm; straight, stiff, not much undulate and reflexed to recurved;

margins entire;

hyaline cells on convex surface with a few end pores, but mostly numerous small to very small (often barely visible) pores or wall thinnings free from the commissures, on concave surface similar, but with pores generally fewer and larger; chlorophyllous cells triangular in transverse section, just reaching concave surface or slightly enclosed.

Sexual condition

dioicous.

dioicous.

Spores

18–33 µm, coarsely papillose on both surfaces;

proximal laesura less than 0.4 spore radius.

18–27 µm;

both surfaces covered with rough, irregular verrucate plates of papillae, bifurcated Y-mark sculpture on distal surface;

proximal laesura less than 0.5 spore radius.

Branch

fascicles with 2 spreading and 1–2 pendent branches.

fascicles with 2 spreading and 2 pendent branches.;

branch stems green, with cortex enlarged with conspicuous retort cells.

Sphagnum rubellum

Sphagnum obtusum

Phenology Capsules mature mid summer.
Habitat Poor fens and ombrotrophic mires, forming extensive carpets and hummocks Forming carpets in minerotrophic peatlands
Elevation low to high elevations low to moderate elevations
Distribution
from FNA
AK; CT; IL; IN; MA; MD; ME; MI; MN; NC; NH; NJ; NY; OH; OR; PA; RI; VT; WA; WI; BC; NB; NF; NS; NT; ON; PE; QC; YT; Greenland; Eurasia
[WildflowerSearch map]
from FNA
AK; MN; AB; BC; MB; NF; NT; NU; ON; QC; SK; YT; Greenland; Eurasia
Discussion

Sporophytes are uncommon in Sphagnum rubellum. This common species is associated with S. angustifolium, S. capillifolium, S. fallax, S. fuscum, S. magellanicum, S. papillosum, S. recurvum, and S. tenellum. Inland, it has a greater tendency to form extensive carpets and floating mats than hummocks. See also discussion under 65. S. andersonianum, 68. S. bartlettianum, and 86. S. talbotianum.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Sporophytes are uncommon in Sphagnum obtusum. This is a quite phenotypically variable species that warrants further investigation, which may result in taxonomic splitting. The strongly obtuse stem leaf should separate it from any similar species with which it occurs. Sphagnum mendocinum looks similar phenotypically but there appears to be no range overlap with S. obtusum. The tiny branch leaf pores, which may seem like no more than pinpricks in the cell surface, easily separate S. obtusum microscopically from other species of sect. Cuspidata.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 27, p. 96. FNA vol. 27, p. 73.
Parent taxa Sphagnaceae > Sphagnum > sect. Acutifolia Sphagnaceae > Sphagnum > sect. Cuspidata
Sibling taxa
S. affine, S. alaskense, S. andersonianum, S. angermanicum, S. angustifolium, S. annulatum, S. aongstroemii, S. arcticum, S. atlanticum, S. austinii, S. balticum, S. bartlettianum, S. beothuk, S. bergianum, S. brevifolium, S. capillifolium, S. carolinianum, S. centrale, S. compactum, S. contortum, S. cribrosum, S. cuspidatum, S. cyclophyllum, S. fallax, S. fimbriatum, S. fitzgeraldii, S. flavicomans, S. flexuosum, S. fuscum, S. girgensohnii, S. henryense, S. imbricatum, S. inexspectatum, S. inundatum, S. isoviitae, S. jensenii, S. junghuhnianum, S. kenaiense, S. lenense, S. lescurii, S. lindbergii, S. macrophyllum, S. magellanicum, S. majus, S. mcqueenii, S. mendocinum, S. microcarpum, S. mirum, S. mississippiense, S. molle, S. obtusum, S. oregonense, S. orientale, S. pacificum, S. palustre, S. papillosum, S. perfoliatum, S. perichaetiale, S. platyphyllum, S. portoricense, S. pulchrum, S. pylaesii, S. quinquefarium, S. recurvum, S. riparium, S. rubiginosum, S. rubroflexuosum, S. russowii, S. sitchense, S. splendens, S. squarrosum, S. steerei, S. strictum, S. subfulvum, S. subnitens, S. subsecundum, S. subtile, S. talbotianum, S. tenellum, S. tenerum, S. teres, S. torreyanum, S. trinitense, S. tundrae, S. viride, S. warnstorfii, S. wilfii, S. wulfianum
S. affine, S. alaskense, S. andersonianum, S. angermanicum, S. angustifolium, S. annulatum, S. aongstroemii, S. arcticum, S. atlanticum, S. austinii, S. balticum, S. bartlettianum, S. beothuk, S. bergianum, S. brevifolium, S. capillifolium, S. carolinianum, S. centrale, S. compactum, S. contortum, S. cribrosum, S. cuspidatum, S. cyclophyllum, S. fallax, S. fimbriatum, S. fitzgeraldii, S. flavicomans, S. flexuosum, S. fuscum, S. girgensohnii, S. henryense, S. imbricatum, S. inexspectatum, S. inundatum, S. isoviitae, S. jensenii, S. junghuhnianum, S. kenaiense, S. lenense, S. lescurii, S. lindbergii, S. macrophyllum, S. magellanicum, S. majus, S. mcqueenii, S. mendocinum, S. microcarpum, S. mirum, S. mississippiense, S. molle, S. oregonense, S. orientale, S. pacificum, S. palustre, S. papillosum, S. perfoliatum, S. perichaetiale, S. platyphyllum, S. portoricense, S. pulchrum, S. pylaesii, S. quinquefarium, S. recurvum, S. riparium, S. rubellum, S. rubiginosum, S. rubroflexuosum, S. russowii, S. sitchense, S. splendens, S. squarrosum, S. steerei, S. strictum, S. subfulvum, S. subnitens, S. subsecundum, S. subtile, S. talbotianum, S. tenellum, S. tenerum, S. teres, S. torreyanum, S. trinitense, S. tundrae, S. viride, S. warnstorfii, S. wilfii, S. wulfianum
Synonyms S. acutifolium var. tenellum, S. capillaceum var. tenellum, S. capillifolium var. tenellum
Name authority Wilson: Bryol. Brit., 19. (1855) Warnstorf: Bot. Zeitung (Berlin) 35: 478. (1877)
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