Pohlia nutans |
Pohlia rabunbaldensis |
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nodding pohlia, nodding thread-moss, pohlia moss |
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Habit | Plants small to large, green or rarely reddish, dull. | Plants small, green to light green, dull. |
Stems | 0.5–3.5(–10) cm. |
0.5–1 cm. |
Leaves | erect to ± spreading, lanceolate to ovate-lanceolate, 2 mm; base not or scarcely decurrent; margins subentire or more often serrulate to serrate in distal 1/3; costa subpercurrent, percurrent, or rarely short-excurrent; distal medial laminal cells hexagonal to rhomboidal, firm, 50–90 µm, walls moderately thick. |
± spreading, slightly contorted when dry, lanceolate to ovate-lanceolate, 0.9–1.2 mm; margins serrulate to serrate in distal 1/3; costa subpercurrent; distal medial laminal cells rhombic to rhomboidal, 45–95 µm, walls thin. |
Seta | orange to orange-brown. |
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Sexual condition | paroicous, rarely dioicous; perigonial leaves ovate-lanceolate; perichaetial leaves somewhat differentiated, ± long-lanceolate. |
unknown, presumed dioicous. |
Capsule | inclined 80–100°, orange to orange-brown, slender-pyriform, neck 1/2 urn length; exothecial cells elongate-rectangular, walls straight; stomata superficial; annulus present; operculum conic; exostome teeth yellow to orange-brown, acute-triangular; endostome hyaline or rarely orange-brown, basal membrane 1/2 exostome length, segments tapered apically, broadly keeled, broadly perforate, cilia short to long. |
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Spores | 16–22 µm, finely to distinctly roughened. |
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Specialized | asexual reproduction typically absent. |
asexual reproduction usually present when sterile; axillary gemmae single, narrowly bulbiform, orange to orange-red, leaf primordia at apex and lower, sometimes to base, laminate, large, flexuose. |
Sporophytes | unknown. |
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Pohlia nutans |
Pohlia rabunbaldensis |
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Phenology | Capsules mature spring (Apr–Jun). | |
Habitat | Soil banks, logs, tree bases, disturbed places | Acid, gravelly to sandy soil along trails |
Elevation | low to high elevations | high elevations |
Distribution |
AK; AL; AR; AZ; CA; CO; CT; DC; DE; FL; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SC; SD; TN; TX; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NB; NL; NS; NT; NU; ON; PE; QC; SK; YT; Africa; Greenland; Eurasia; Mexico (Nuevo León); Australia
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GA; NC |
Discussion | Pohlia nutans is the most common species of Pohlia in North America, Europe, and elsewhere in the Northern Hemisphere. In contrast to the treatment by A. J. Shaw (1982), P. sphagnicola is not separated here from P. nutans; the type of P. sphagnicola is European. Plants referable to P. sphagnicola, including North American collections, differ in being dioicous and having entire leaves, slightly shorter laminal cells, and smaller spores. The habitat in Sphagnum hummocks is not diagnostic; at least 80% of plants growing in Sphagnum are P. nutans. Pohlia schimperi, a northern form with reddish leaves, also dioicous, is not recognized, as per Shaw. The peristome of Pohlia nutans is as well developed as any in Pohlia, with long, tapered, trabeculate exostome teeth and well-developed endostomes with broadly keeled, widely perforate segments and short to long cilia. The laminal cells are short- to elongate-hexagonal with thickened walls. The only other North American species with relatively thick-walled laminal cells is P. elongata; the cells of P. elongata are typically longer, but there is extensive overlap in sizes. Plants without sporophytes have generally been named P. nutans, although some collections from montane regions may actually be P. elongata; sporophytes of P. elongata have longer necks, as long as or longer than the urns, and reduced peristomes with endostome segments narrowly split along the keel and (usually) no cilia. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Pohlia rabunbaldensis has bulbiform gemmae occurring singly in a leaf axil, similar to those of P. drummondii, but the leaf primordia are even larger relative to the gemma body. Plants of P. rabunbaldensis are slender, with dull leaves much like those of P. annotina, somewhat contorted when dry, distinct from the broader, carinate, somewhat shiny leaves of P. drummondii, which are unchanged on drying. of conservation concern (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 28, p. 196. | FNA vol. 28, p. 204. |
Parent taxa | Mielichhoferiaceae > Pohlia | Mielichhoferiaceae > Pohlia |
Sibling taxa | ||
Synonyms | Webera nutans, P. sphagnicola | |
Name authority | (Hedwig) Lindberg: Musc. Scand., 18. (1879) | A. J. Shaw: Bryologist 108: 180, fig. 2. (2005) |
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