Sphagnum cuspidatum |
Sphagnum henryense |
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feathery bog-moss, feathery peat-moss, tooth sphagnum |
Henry's sphagnum |
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Habit | Plants slender and weak-stemmed, moderate-sized, flaccid and plumose in aquatic forms to more compact in emergent forms, spreading branches often conspicuously falcate, giving capitulum a twisted appearance; green to yellow, often tinged with red, red-brown or brown in capitula. | Plants moderate-sized to robust, capitulum typically flat, ± 5-radiate and with terminal bud slightly visible; green, pale green, to pale pinkish brown tinged with brown to reddish brown; forming carpets or low hummocks. |
Stem(s) | leaves triangular-ovate, more than 1.2 mm, usually appressed; apex acute to apiculate, hyaline cells rarely septate or porose, apical region often fibrillose. |
leaves to 1.9 × 1 mm; rarely hemiisophyllous; hyaline cells non-ornamented, nonseptate or septate. |
Branches | mostly unranked to weakly 5-ranked, often conspicuously falcate, leaves greatly elongated at distal end. |
± tapering to a point, leaves spreading to moderately imbricate. |
Branch leaves | ovate-lanceolate to lanceolate, 1.6–5 mm, falcate toward branch tips, when dry often undulate and recurved, rarely weakly serrulate along the margins in submerged forms, leaves from middle of spreading branches with length to width ratio less than or equal to 1:0.28; hyaline cells length to width ratio in apical convex surface region 8:1 or more, convex surface with 0–1 small round pores at apex, concave surface with faint round wall thinnings in cell apices and angles; chlorophyllous cells triangular to trapezoidal in transverse section, broadly exposed on the convex surface and exposed slightly on the concave surface. |
ovate, to 2.7 × 1 mm; hyaline cells on convex surface with numerous small round pores along the commissures, cell walls overlying chlorophyll cells often with a network of irregular worm like ridges although they may be lacking; chlorophyllous cells isosceles-triangular to narrowly ovate triangular in transverse section and just enclosed on convex surface,end wall not thickened. |
Sexual condition | dioicous. |
dioicous. |
Capsule | with numerous pseudostomata. |
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Spores | 29–38 µm; covered with large papillae on both surfaces, appearing pusticulate; proximal laesura less than 0.5 spore radius. |
24–29 µm; surface finely papillose to nearly smooth. |
Branch | fascicles with 2 spreading and 2–3 pendent branches.; branch stems green, but often pinkish at the proximal ends, with cortex enlarged with conspicuous retort cells. |
fascicles with 2 spreading and 2 pendent branches.; branch stems with hyaline cells non-ornamented; funnel-like projections absent from interior end walls, large round pores on superficial walls. |
Sphagnum cuspidatum |
Sphagnum henryense |
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Habitat | Widespread forming wet carpets in ombrotrophic to weakly minerotrophic mires | Poor to medium fens, common in wooded fens and pond margins |
Elevation | low to moderate elevations | low to moderate elevations |
Distribution |
AL; CT; DE; FL; GA; IL; IN; KS; MA; MD; ME; MI; MN; MS; NC; NH; NJ; NY; OH; PA; RI; SC; TN; VA; VT; WI; WV; NB; NF; NS; ON; QC; Europe
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AK; AL; AR; CA; CT; DC; DE; FL; GA; IL; IN; LA; MA; MD; ME; MI; MO; MS; NC; NH; NJ; NY; OH; OK; OR; SC; TN; TX; VA; VT; WI; WV; BC; NF; NS; PE; Asia |
Discussion | Distinguishing Sphagnum cuspidatum from S. viride is sometimes difficult, as both occur over a similar geographic range and both grow in wet carpets. Sphagnum cuspidatum has narrower branch leaves and usually a distinct red tinge at the branch bases within the capitulum. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
The typical form of Sphagnum henryense is a large plant with a quite flat capitulum with a small terminal bud. Microscopically, typical material has distinct ridges on the branch leaf hyaline cells and relatively small and round pores on the branch leaf hyaline cell convex surface. Sphagnum palustre, which has the same branch leaf chlorophyll cell cross section, typically has smooth hyaline cell walls and hyaline cell pores that are larger and more elliptical in shape. However, Sphagnum species are plastic phenotypically and it is common to find plants that cannot be reliably assigned to either S. henryense or S. palustre. For example, some species of Sphagnum that are relatively easy to distinguish on other characteristics, such as S. papillosum, S. alaskense and S. affine, may occasionally completely lack any hyaline cell ornamentation or display it in reduced form. Since these can be distinguished on other characters, the species are still readily identifiable, but when S. henryense lacks the ornamentation, there is no other solid character to distinguish it from S. palustre. Thus, although we can find material from both North American coasts that has good ornamentation (R. E. Andrus 1980), there is much other material that looks in other respects like S. henryense but lacks the ornamentation. Barring taxonomy beyond microscopic examination, many collections of henryense/palustre will of necessity not be absolutely identifiable. Where their ranges overlap, mixed stands may often be found. We believe that the species are still good, but accurate delimitation of their distinctive ecologies and ranges will be very problematic. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 27, p. 66. | FNA vol. 27, p. 51. |
Parent taxa | Sphagnaceae > Sphagnum > sect. Cuspidata | Sphagnaceae > Sphagnum > sect. Sphagnum |
Sibling taxa | ||
Synonyms | S. cuspidatum var. plumosum, S. faxonii, S. virginianum | S. henryense var. bartlettii |
Name authority | Hoffman: Deutschl. Fl. 2: 22. (1796) | Warnstorf: Hedwigia 39: 107. (1900) |
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