Sphagnum papillosum |
Sphagnum andersonianum |
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fat peat-moss, papillose sphagnum |
Anderson's sphagnum |
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Habit | Plants moderate-sized to fairly robust; strong-stemmed and generally compact, capitulum usually not much enlarged; greenish brown to deep golden brown; forming compact carpets in floating mats and depressions as well as dense stands on hummock sides and low hummocks. | Plants small, soft and slender; capitulum small; pale pink to pale purplish red; without metallic lustre when dry. |
Stem(s) | leaves to 1.3 × 0.7 mm; rarely hemiisophyllous; hyaline cells non-ornamented, mostly septate. |
leaves lingulate, 0.9–1.2(–1.4) mm, apex rounded-erose to sometimes slightly apiculate, border moderately strong and broadened at the base (to 0.8 the width); hyaline cells rhombic, 0–1-septate, usually efibrillose. |
Branches | generally short and blunt, leaves spreading. |
not or slightly 5-ranked, lax. |
Branch leaves | broadly ovate, 1.7 × 1 mm; hyaline cells on convex surface with round to elliptic pores along the commissures, hyaline cell walls covered with papillae where overlying chlorophyllous cells; chlorophyllous cells trapezoidal to truncate-elliptic in transverse section, equally exposed on both surfaces or less exposed on convex surface, end walls thickened. |
ovate, 0.8–1.4 mm, distinctly concave, straight, apex dentate and involute; border entire; hyaline cells on convex surface with elliptic pores along the commissures, grading from smaller pores near the apex to larger pores at the base, concave surface with large round pores on the proximal portions of the leaf. |
Sexual condition | dioicous. |
dioicous. |
Capsule | with numerous pseudostomata. |
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Spores | 26–36 µm; more roughly papillose on distal surface than proximal surface, distinct raised, bifurcated-Y mark sculpture on distal surface; proximal laesura 0.5 spore radius or more. |
18–24 µm; coarsely papillose on both surfaces; proximal laesura less than 0.5 the length of the spore radius. |
Branch | fascicles with 2 spreading and 2–3 pendent branches.; branch stems with hyaline cells non-ornamented, no or weak funnel-like projections on the interior end walls, mostly with 1 pore per cell on superficial cell wall. |
fascicles with 2 spreading and 1–2 pendent branches. |
Sphagnum papillosum |
Sphagnum andersonianum |
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Phenology | Capsules mature mid to late summer. | |
Habitat | Very common in very poor to poor fen mire habitats where it is often a major peat former, but scarce to absent in truly ombrotrophic peatlands sites | Weakly minerotrophic |
Elevation | low to moderate elevations | low to moderate elevations |
Distribution |
AK; CA; CT; DE; IL; IN; MD; ME; MI; MN; NC; NH; NJ; NY; OH; OR; PA; SC; VT; WA; WI; WV; BC; NB; NF; NS; ON; PE; QC; YT; Eurasia
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AK; CT; MA; ME; NH; NY; RI; VT; BC; NF; NS; QC; Europe |
Discussion | Sphagnum papillosum is often easily field-identifiable by its rich golden brown to dark brown color and short, blunt branches. Nearly all specimens have the papillae on the branch leaf chorophyll cells but a few smooth forms have been found. Such forms will have stem leaves with divided hyaline cells whereas in the confusable species S. palustre and S. centrale such cells are rare or absent. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Sporophytes are uncommon in Sphagnum andersonianum. Its distribution is uncertain due to past taxonomic confusion with S. rubellum, S. capillifolium, and other closely related species in sect. Acutifolia. This is one of the most hydrophytic species of the section and is often associated with S. angustifolium, S. fallax, and S. rubellum. It is often not easily distinguished from S. rubellum, with which it may intergrade in a manner similar to that already demonstrated for S. rubellum and S. capillifolium by N. Cronberg (1997, 1998). Phenotypically S. andersonianum is a softer, paler plant with branch leaves that are more ovate and concave on branches that are less 5-ranked. Sphagnum rubellum also has the branch leaves sometimes subsecund while in S. andersonianum they are straight. Ecologically S. rubellum is an open mire species of usually ombrotrophic conditions, where it often forms hummocks, while S. andersonianum occurs in more sheltered sites where there is some mineral influence. Where they occur together, S. rubellum is on the tops of hummocks and S. andersonianum is on the hummock sides and bases. Microscopically S. rubellum has stem leaves with at least some of the hyaline cells twice septate, while in S. andersonianum none are twice septate. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 27, p. 53. | FNA vol. 27, p. 88. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | S. cymbifolium var. papillosum, S. papillosum var. laeve, S. papillosum var. sublaeve, S. waghornei | |
Name authority | Lindberg: Acta Soc. Sci. Fenn. 10: 280. (1872) | R. E. Andrus: Bryologist 83: 60, figs. 1–7. (1980) |
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