Sphagnum lescurii |
Sphagnum platyphyllum |
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Lescur's sphagnum |
flat-leaf peat-moss, sphagnum |
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Habit | Plants moderate-sized to robust; upright, prostrate, or aquatic; green, pale yellow, golden brown, dark brown, tinged with red in exposed sites and purplish in aquatic forms; capitulum rounded and often strongly twisted. | Plants small to moderate-sized, unbranched or sparsely branched; green, golden brown to brown, capitulum small with a large and conspicuous terminal bud. |
Stem(s) | leaves lingulate to ovate-lingulate, 1.3–2 mm; apex truncate to rounded, usually denticulate; hyaline cells typically fibrillose for 1/2 of leaf or more, often 1–2-septate, convex surface with 4–12 or more pores per cell along the commissures, concave surface with fewer pores. |
leaves broadly ovate, 1.2–2.2 mm; straight; apex rounded; hyaline cells non-septate, convex surface with numerous small pores (less than or equal to 1/6 cell diameter) forming a continuous row along the commissures, concave surface aporose or with a few scattered pores along the commissures and cell ends. |
Branches | usually curving, often large and tumid. |
short and blunt, sometimes lacking completely and plants simplex. |
Branch leaves | broadly ovate to ovate-lanceolate, 1.3–2.5 mm, greatly elongated in aquatic forms, straight or infrequently subsecund or subsquarrose; hyaline cells with 10–22 pores along the commissures on the convex surface, no or fewer pores per cell (1–8) on the concave surface. |
broadly ovate, 1.4–2.5(–3) mm; straight; apex rounded; hyaline cells as in stem leaf. |
Sexual condition | dioicous. |
dioicous. |
Capsule | exserted, with few pseudostomata. |
exserted, with few pseudostomata. |
Spores | 27–34 µm; finely papillose on both surfaces, with distinct raised Y-mark sculpture (indistinctly bifurcated Y-mark) on the distal surface; proximal laesura less than 0.5 spore radius. |
23–35 µm; papillose on both surfaces, with indistinct Y-mark sculpture on distal surface; proximal laesura 0.5 spore radius or less. |
Branch | fascicles with 2(rarely 3) spreading and 1–2(–3) pendent branches. |
fascicles of 1–3 branches, 1–2 of these spreading, branches usually not numerous. |
Sphagnum lescurii |
Sphagnum platyphyllum |
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Phenology | Capsules mature late spring to early summer. | |
Habitat | Weakly minerotrophic in a broad range of wetlands, often of an aquatic or periodically dried character | Typically growing in minerotrophic habitats such as shores of lakes, ponds, streams, flarks of string mires, margins of open fens, especially seasonally flooded sites |
Elevation | low to moderate elevations | low to high elevations |
Distribution |
AL; AR; CT; DC; DE; FL; GA; IA; IL; IN; KY; LA; MA; MD; ME; MI; MN; MO; MS; NC; NH; NJ; NY; OH; OK; PA; RI; SC; TN; TX; VA; VT; WI; WV; NF; NS; Europe
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AK; AZ; CA; CO; CT; IN; MA; ME; MI; MN; MT; NH; NJ; NY; OH; OR; RI; VT; WI; WY; AB; BC; MB; NB; NF; ON; QC; YT; South America; Greenland; Eurasia |
Discussion | Sporophytes are uncommon in Sphagnum lescurii, which may be the most phenotypically variable of all the North American Sphagnum species, and quite probably deserves some taxonomic splitting. The tremendous phenotypic plasticity of this species, however, makes it quite difficult to sort out the genotypic component of variability, and thus most sphagnologists since Warnstorf have avoided the temptation of splitting and have instead treated this as one very variable species. This is the approach maintained in this treatment. We have also chosen not to use the earlier name S. denticulatum because its type is a phenotypic morphotype not clearly assignable to the current concept of either S. auriculatum or S. lescurii (K. I. Flatberg, pers. comm.). Some of the American material assignable to S. lescurii is quite likely the same as the European species S. auriculatum, but much of our material is certainly not the same. Until more definitive data are available, we have chosen to continue to use the name S. lescurii. The large stem leaf will generally distinguish this from similar species of sect. Subsecunda. See also discussion under 55. S. inundatum and 61. S. platyphyllum. The names Sphagnum alabamae Warnstorf, S. aquatile Warnstorf, S. obesum (Wilson) Warnstorf, S. rufescens (Nees & Hornschuch) Warnstorf, and S. turgidulum Warnstorf also have been applied to this taxon. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Sporophytes are uncommon in Sphagnum platyphyllum, which can be quite variable in size and the development of branch fascicles, with some forms even being simplex while other forms may have up to three branches per fascicle. The species can usually be recognized by the large stem leaves that are spreading and easily visible because of the scarcity of hanging branches. It should also be noted that in this species and S. contortum the 2–3-layered stem cortex is not an entirely consistent trait, as plants quite typical in all other respects are occasionally found with the cortex only 1-layered, at least in part. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 27, p. 81. | FNA vol. 27, p. 83. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | S. orlandense, S. plicatum, S. wieboldtii | S. laricinum var. platyphyllum, S. contortum var. platyphyllum, S. subsecundum var. platyphyllum |
Name authority | Sullivant: in A. Gray, Manual ed. 2, 611. (1856) | (Lindberg) Warnstorf: Flora 67: 481. (1884) |
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