Didymodon australasiae |
Didymodon maschalogena |
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Michigan beard moss |
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Habit | Plants usually blackish green. | Plants green to glossy green. |
Stem(s) | leaves spreading-incurved and twisted to incurved-appressed when dry, spreading to spreading-recurved and not keeled when moist, monomorphic, short-lanceolate or sometimes short-ovate to long-elliptic, broadly concave adaxially across leaf, usually 1–2.5 mm, base scarcely differentiated in shape to ovate, margins usually recurved at mid leaf, entire, apex broadly acute or occasionally narrowly so, not fragile; costa percurrent or ending a few cells below the apex, broader at mid leaf, occasionally weakly spurred, with a low adaxial pad of cells, adaxial costal cells quadrate, 4–6 cells wide at mid leaf, guide cells in 1–2 layers; basal laminal cells differentiated medially or across leaf, quadrate to short-rectangular, walls very thin and not perforated; distal laminal cells 7–12 wide, 1:1 or occasionally transversely elongate below, papillae usually distinct, low or simple to 2-fid, occasionally absent, lumens oval to rounded-quadrate, walls thin to evenly thickened, convex on both sides of lamina, 2-stratose in one or more rows along margins. |
leaves catenulate-incurved when dry, spreading and weakly keeled when moist, monomorphic, ovate-lanceolate, adaxially grooved in distal third, 0.9–1.1 mm, base often but not always sharply differentiated in shape, ovate, margins narrowly to broadly recurved in proximal 1/3–1/2, entire, apex narrowly acute, abruptly acuminate, not fragile; costa percurrent to very shortly excurrent, tapering, widened pad of cells absent, adaxial costal cells elongate, 4 cells wide at mid leaf, guide cells in 1 layer; basal laminal cells little differentiated, quadrate or very short-rectangular, walls thickened and lumens usually oval; distal laminal cells 7–9(–12) µm wide, 1:1, papillae absent to low, simple, lumens subquadrate to oval, walls irregularly thickened, convex on both sides, 1-stratose. |
Seta | 0.7–1 cm. |
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Sexual condition | sterile in range of flora. |
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Capsule | 1–1.9 mm; peristome teeth 32, linear, weakly twisted, to 600 µm, occasionally rudimentary. |
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Spores | 11–15 µm. |
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Specialized | asexual reproduction by multicellular tubers on proximal rhizoids. |
asexual reproduction by multicellular spheric gemmae in leaf axils. |
Distal | laminal KOH reaction variously negative or yellow- or orange- or red-brown. |
laminal KOH reaction yellow- or orange-brown. |
Sporophytes | not seen. |
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Didymodon australasiae |
Didymodon maschalogena |
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Phenology | Capsules mature winter–spring. | |
Habitat | Soil, gypsum, acid rock, ledges, sandstone, silt | Soil, rock, spray zone |
Elevation | moderate to high elevations (300-2000 m) (moderate to high elevations (1000-6600 ft)) | low to high elevations |
Distribution |
AZ; CA; CO; NM; NV; OR; TX; Mexico; Central America; South America; Europe; n Africa; s Africa; Pacific Islands (New Zealand); Australia |
MI; BC; NT; Mexico; Greenland; Asia; Atlantic Islands (Cape Verde); Indian Ocean Islands (Reunion) |
Discussion | In North American Didymodon, hydroids are found in the costae of D. anserinocapitatus, D. australasiae, D. nevadensis, D. norrisii, D. umbrosus, D. revolutus, and D. vinealis, and in these species the adaxial stereid band is usually absent in well developed specimens. Intergrades exist between D. australasiae and D. umbrosus, but the extreme forms are common and quite distinctive. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
The significant characters of Didymodon maschalogena are the small size of the leaves, which are catenulate, and the presence of propagula; the appearance of the areolation cannot distinguish this species from many congeners but is clearly in longitudinal rows. The species is apparently widespread but of spotty distribution. It was long known as D. michiganensis, but J.-P. Frahm et al. (1996) recently found an earlier name. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 27, p. 547. | FNA vol. 27, p. 558. |
Parent taxa | Pottiaceae > subfam. Barbuloideae > Didymodon | Pottiaceae > subfam. Barbuloideae > Didymodon |
Sibling taxa | ||
Synonyms | Tortula australasiae, D. diaphanobasis, Husnotiella torquescens, Trichostomopsis australasiae, Trichostomopsis brevifolia, Trichostomopsis diaphanobasis, Trichostomopsis fayae | Barbula maschalogena, Barbula michiganensis, D. michiganensis |
Name authority | (Hooker & Greville) R. H. Zander: Phytologia 41: 21. (1978) | (Renauld & Cardot) Brotherus: in H. G. A. Engler and K. Prantl, Nat. Pflanzenfam. 234/235[I,3]: 1192. (1909) |
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