The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

sphagnum

fringe bogmoss, fringe peat-moss, sphagnum

Habit 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. Plants typically small and slender, larger and compact in the Arctic, capitulum small to moderate-sized, often with a conspicuous terminal bud; green, yellowish brown to brown; without metallic lustre when dry.
Stem(s)

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.

leaves spatulate to broad-spatulate, 0.8–1.5(–2) mm, strongly lacerate across the broad apex and often part way down the margins, border scarcely to strongly broadened at base (0.25 width of base or less);

hyaline cells rhomboid, efibrillose and often 1–2-septate.

Branches

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

not 5-ranked, quite terete, long, and slender Branch fascicles with 1– 2 spreading and 1–2 pendent branches.

Branch leaves

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.

ovate to ovate-lanceolate; 1.1–1.5(–2) mm, slightly concave, straight;

apex involute;

margins entire;

hyaline cells on convex surface with numerous pores along the commissures grading from small pores near leaf apex to large pores at base, concave surface with large round pores at leaf apex and along margins.

Sexual condition

dioicous.

often monoicous.

Spores

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.

20–27 µm, finely papillose on both surfaces;

proximal laesura less than 0.5 spore radius.

Branch

fascicles with 2 spreading and 2 pendent branches.;

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

Sphagnum obtusum

Sphagnum fimbriatum

Habitat Forming carpets in minerotrophic peatlands
Elevation low to moderate elevations
Distribution
from FNA
AK; MN; AB; BC; MB; NF; NT; NU; ON; QC; SK; YT; Greenland; Eurasia
from USDA
North America; South America; Eurasia; Pacific Islands (New Zealand)
[WildflowerSearch map]
Discussion

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.)

Subspecies 2 (2 in the flora).

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

Key
1. Plants small and slender, capitulum small and with a conspicuous terminal bud; stem leaves fimbriate down the sides and weakly to moderately bordered at the base
subsp. fimbriatum
1. Plants moderate-sized and compact, capitulum moderate sized and lacking a conspicuous terminal bud; stem leaves entire down the sides and strongly bordered at the base
subsp. concinnum
Source FNA vol. 27, p. 73. FNA vol. 27, p. 92.
Parent taxa Sphagnaceae > Sphagnum > sect. Cuspidata Sphagnaceae > Sphagnum > sect. Acutifolia
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. 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
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. 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. 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
Subordinate taxa
S. fimbriatum subsp. concinnum, S. fimbriatum subsp. fimbriatum
Name authority Warnstorf: Bot. Zeitung (Berlin) 35: 478. (1877) Wilson & Hooker: in J. D. Hooker, Fl. Antarct., 398. (1847)
Web links