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Sphagnum affine

(Sphagnum)

Common Names

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Common Names in English:

Sphagnum

Description

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Family Sphagnaceae

Plants with branches in fascicles, branches usually of spreading and pendent types but rarely spreading only. Protonemata thallose . Leaves usually of two distinctly different types; branch leaves that are normally inrolled and broadest ca. 1/4-1/3 the distance from the base , more or less tapered to a cucullate to involute apex; stem leaves more or less flat and usually broadest at the base; both leaf types of a network of hyaline , dead cells and green chlorophyllose cells; pores and reinforcing fibrils frequent in branch leaf hyaline cells and uncommon in stem leaf hyaline cells. Rhizoids lacking. Sporophytes consisting of a spherical capsule with pseudostomata on capsule surface, a very short seta , and a foot , exserted on a pseudopodium of gametophyte tissue . Spores released by explosive opening of operculum .

Genus 1, species ca. 285: nearly worldwide.

The sphagnum mosses, or peat mosses, are unique not only morphologically but also ecologically. With their abundant clear cells they can retain up to 25 times their dry weight in water, and a uniquely strong acidifying power permits sphagnum to direct succession wherever conditions are suitable for them to flourish. Much of the earth's surface with a cool humid climate is dominated, thus, by sphagnum peatlands.[1]

Genus Sphagnum

Plants typically with upright stems, young branches arranged spirally around stem at growing apex into a capitulum, branches clustered into fascicles along stem, stem and branch leaves of alternating inflated , S-shaped to rhomboid hyaline cells and narrow linear chlorophyllous cells, hyaline cells typically fibrillose and porose on branch leaves. Protonema typically 1-stratose, gametophyte developing from lateral margin . Stems differentiated into a central cylinder of thin-walled parenchymatous cells, merging into a cylinder of thick-walled cortical cells surrounded by 0-4 layers of thin-walled inflated cells, superficial layer of cells usually aporose, but may be porose. Stem leaves may be less fibrillose or efibrillose and less porose or aporose than the branch leaves, often septate , a distinct border of narrow linear chlorophyllous cells often along margins and at base , and with a greater width :length ratio than branch leaves in anisophyllous forms, partly differentiated in hemiisophyllous forms, and identical in isophyllous forms. Branches typically dimorphic as spreading and pendent branches, but some species lack branches or branches are not clearly differentiated, pendent branches typically more slender than spreading branches and with a tendency to adhere to and cover the stem. Branch fascicles typically with 2 spreading and 1-2 pendent branches, but there may be up to 12(-14) per fascicle. Branch stems typically green, with a superficial layer of inflated retort cells; these grouped or solitary, usually porose at the distal end with a conspicuous or inconspicuous neck. Branch leaves with 2/5 phyllotaxy, of a 1-stratose network of alternating chlorophyllous and hyaline cells; hyaline cells usually S-shaped, rarely rhomboid, nearly always strengthened with conspicuous spiral fibrils , small to large, round to elliptic and sometimes ringed pores occur along commissures or rarely on cell lumen, convex surface typically with more pores per cell than concave surface; chlorophyllous cells may be enclosed on both surfaces, more broadly exposed on one surface or equally exposed on both surfaces as viewed in transverse section , adjacent cell walls typically smooth , but various types of cell wall projections may be clearly visible in transverse section. Sexual condition dioicous or monoicous; stalked globose antheridia borne at the tips of branches usually with swollen colored tips of branches near capitulum; long-necked archegonia borne on short branches singly surrounded by perichaetial leaves that are typically longer than branch leaves. Capsule spherical , brown to black, lacking an annulus or peristome with a operculum convex; spore sac amphithecial in origin , over-arching columella. Calyptra membranous. Spores tetrahedral , with prominent trilete mark , fine to coarse superficial surface, distal surface may have raised Y-mark, bifurcated Y-mark sculpture, or none.

Species 285: worldwide except Antarctica, primarily in boreal regions but also in cool, moist montane and oceanic habitats such as nutrient-poor and acidic wetlands and mires .

The concept of species in Sphagnum is controversial. We have followed P. Isoviita (1966) and K . I. Flatberg (1994) in the recognition of species. H. A. Crum (1984) and others (R. E. Daniels and A. Eddy 1985; A. L. Andrews 1958, 1959) have adopted more conservative taxonomic concepts for species in the Northern Hemisphere. Description of the spores above is from Cao T. and D. H. Vitt (1986) ; for additional discussion of the protonema see C. B . McQueen (1988).

Microscopic features can be observed by using a concentrated aqueous or alcohol solution of Crystal Violet. A 50% solution of alcohol and Methylene Blue or Safranin Red can be used, but these usually do not stain features such as minute pores, fibrils, wall thinnings , and surface sculpture on the chlorophyllous cells. The number and kinds of branches should be determined, individual stem and branch leaves (from the middle of a spreading branch) should be examined from the distal 2 cm of the plant, and the superficial surface of stem cortical cells as well as cross sections of branch leaves and stems may need examination.[2]

Physical Description

Species Sphagnum affine

Plants moderate-sized and lax to somewhat compact , ± stiff-stemmed; moderate-sized to large, forming lawns or low, loose hummocks; green, yellow-brown to golden brown and often tinged with brown to purplish brown; capitulum ± flat in lax open-grown forms to ± rounded and compact in open-grown forms. Stems brown, superficial cortical layer with spiral reinforcing fibrils clearly visible, usually 2 or more pores per cell , comb-fibrils visible on interior wall. Stem leaves to 1.3-1.9 × 0.6-1.2 mm; rarely hemiisophyllous; hyaline cells non-ornamented, nonseptate or sometimes septate . Branches ± tapering, leaves loosely imbricate to spreading and often squarrose in shade forms. Branch fascicles with 2 spreading and 2-3 pendent branches. Branch stems with cortical cell comb-lamellae weakly differentiated on interior wall, no or weak funnel-like projections on the interior end walls, pores in superficial wall mostly restricted to leaf attachments . Branch leaves ovate to ovate elliptical, 1.5-2 × 0.9-1.6 mm; hyaline cells on convex surface with elliptic to more often round pores along the commissures , comb-lamellae can be present, but often absent or restricted to leaf bases ; chlorophyllous cells broadly triangular in transverse section and well-enclosed on the convex surface; end wall not thickened. Sexual condition dioicous. Capsule with scattered pseudostomata. Spores 27-31 µm; granulate on both surfaces; laesura on proximal surface less than 0.5 the spore radius. Capsules fairly common, mature early to late summer. [source]

Sphagnum affine may occur elsewhere but the taxonomy is unclear (K . I. Flatberg 1984). Although species of sect. Sphagnum are notoriously difficult to tell apart in the field , S. affine is typically smaller than S. centrale, S. palustre, and S. papillosum, the other brown species of this section with which it may occur. It is also much more likely to have somewhat squarrose branch leaves, especially in shade forms. [source]

Habit: Nonvascular

Habitat

Widespread and often ruderal , wide variety of minerotrophic wetlands, especially abundant in forested mires ; low to moderate elevations [3].

Typically found at an altitude of 0 to 1,088 meters (0 to 3,570 feet).[4]

Taxonomy

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Unambiguous Synonyms

  1. Sphagnum imbricatum affine (Renauld & Cardot) Flatberg
  2. Sphagnum imbricatum var. affine (Renauld & Cardot) Warnstorf
  3. Sphagnum imbricatum var. laeve Warnstorf

Similar Species

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Members of the genus Sphagnum

There are approximately 637 species in this genus. Here are just 100 of them:

S. aciphyllum · S. acutifolia · S. acutifolioides · S. acutifolium · S. acutifolium meridense · S. acutifolium pallescens · S. acutifolium purpureum · S. acutifolium quinquefarium · S. acutifolium rubrum · S. acutifolium versicolor · S. acutirameum · S. acutum · S. aequalipunctatum · S. aequifolium · S. aequiporosum · S. affine (Sphagnum) · S. africanum · S. alabamae · S. alaskense · S. albescens · S. alegrense · S. algentryi · S. allionii · S. alpinum · S. amazonense · S. amazonicum · S. ambiguum · S. amblyphyllum · S. americanum · S. amoenoides · S. amoenum · S. andersonianum (Anderson's Sphagnum) · S. andinum · S. angermanicum (Angerman's Sphagnum) · S. angustifolium (Sphagnum) · S. annulatum (Sphagnum) · S. antarcticum · S. antarense · S. antillarum · S. antioquiense · S. aongstroemii (Aongstroem's Sphagnum) · S. apiculatum · S. apollinairei · S. aquatile · S. arbogastii · S. arboreum · S. arcticum (Arctic Sphagnum) · S. atroligneum · S. aureum · S. auriculatum · S. austinii (Austin's Sphagnum) · S. australe · S. austro-americanum · S. austro-molle · S. azuayense · S. bahiense · S. balslevii · S. balticum (Baltic Sphagnum) · S. barclayae · S. bartlettianum (Bartlett's Sphagnum) · S. batumense · S. bavaricum · S. beccarii · S. beyrichianum · S. biforme · S. billbuckii · S. bocainense · S. bolanderi · S. boliviae · S. boomii · S. bordasii · S. borneoense · S. bourbonense · S. boyacanum · S. brachybolax · S. brachycaulon · S. brachycladum · S. brasiliense · S. breedlovei · S. brevicaule · S. brevifolium · S. brevirameum · S. buckianum · S. caldense · S. calymmatophyllum · S. campicola · S. capense · S. capillaceum · S. capillaceum tenellum · S. capillifolioides · S. capillifolium (Sphagnum) · S. capillifolium rubellum · S. capillifolium var. tenellum · S. carlottae · S. carneum · S. carolinianum (Carolina Sphagnum) · S. caroliniarum · S. centrale (Sphagnum) · S. ceylonicum · S. chevalieri

More Info

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Further Reading

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Notes

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Contributors

Data Sources

Accessed through GBIF Data Portal November 21, 2007:

Identifiers

Footnotes

  1. Cyrus B. McQueen, Richard E. Andrus "Sphagnaceae". in Flora of North America Vol. 27 Page 45, 102, 108,
    624. Oxford University Press. Online at EFloras.org. [back]
  2. "Sphagnum". in Flora of North America Vol. 27 Page 3, 4, 6, 9, 10, 11, 12, 15, 16, 19, 20, 21, 22, 23, 26, 27, 28, 29, 30, 32, 33,. Oxford University Press. Online at EFloras.org. [back]
  3. "Sphagnum affine". in Flora of North America Vol. 27 Page 48, 49, 50, 51, 52, 55, 92. Oxford University Press. Online at EFloras.org. [back]
  4. Mean = 300.310 meters (985.269 feet), Standard Deviation = 244.570 based on 226 observations. Altitude information for each observation from British Oceanographic Data Centre. [back]
Last Revised: 2009-04-24