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Rhabdoweisiaceae

(Family)

Overview

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A Family in the Kingdom Plantae.

Taxonomy

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The Family Rhabdoweisiaceae is further organized into finer groupings including:

Genera

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Amphidium

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Cynodontium

Plants in loose to dense tufts, dull, dark or yellowish green sometimes brownish. Stems erect, (0.5-) 1-2(-3) cm, simple or forked, slightly to densely radiculose basally, the rhizoids reddish near the stem, often hyaline distally, smooth or roughened, arising from the stems and the base of branches. Leaves crispate when dry, curled-contorted when wet, the limb erect-flexuose from an erect base, ovate- or oblong- or linear-lanceolate, ovate and concave basally, limb distally narrow, keeled to tubulose, gradually acuminate to a fine point; apex acute to obtuse, not deciduous; margins at the base erect and entire, recurved beyond the base or occasionally throughout, nearly entire or evenly to coarsely serrulate in the distal 1/4-1/3 or just at the apex; margins (1-) 2(-3) -stratose, occasionally 2-stratose along costa or scattered; costa single, usually ending before the apex, proximally smooth or sometimes toothed on abaxial surface especially in apical third by projecting cell ends; 7.5-10 µm, adaxial epidermal layer absent, adaxial stereid band poorly developed, guide cells present in 1 row, abaxial stereid band strong, abaxial epidermal layer poorly differentiated from abaxial stereids or absent; basal cells elongate, rectangular, mostly to 5:1, alar cells not or little differentiated; medial and distal laminal cells short, rounded-quadrate to irregular, or short-rectangular, mostly 2:1, longer and broader along costa, occasionally oblate to triangular, smooth or sometimes spinose and bulging mammillose (strongly mammillose-papillose), nonpitted. Specialized asexual reproduction absent. Sexual condition autoicous or cladautoicous; perigonia sessile or stalked, perigonial bracts (2-) 4-6(-7) mm, ovate-lanceolate, concave, smooth, acute to rounded-obtuse, occasionally with recurved tips; perichaetial bracts similar to vegetative leaves or larger. Seta 2-15 mm, smooth, yellow, tending to reddish brown with age, occasionally curved-cygneous when wet, straight when dry [C. gracilescens]. Capsule erect or inclined, oblong, ovoid, cylindric, straight or often arcuate, occasionally zygomorphic, smooth or longitudinally broadly or narrowly striate when moist, becoming more deeply furrowed to sulcate when dry, with or without weakly differentiated to distinct struma; annulus variable, absent, rudimentary, small and adherent or large, 1-3 rows of deciduous, revoluble cells; operculum obliquely high-conic, rostrate to long-rostrate; peristome single, of 16 lanceolate teeth, more or less entire, irregularly perforate or divided about halfway to 2/3 or nearly to the base into two divisions, distinctly vertically striate basally, red, with pale, papillose tips. Calyptra cucullate. smooth. Spores (10-) 15-23(-25) µm, smooth, finely to distinctly papillose.[1] [more]

Dichodontium

Plants forming mats, cushions, or loosely caespitose, dull yellow or green to dark green. Stems 1-5(-8) cm, erect, simple or sparingly branched; sparsely tomentose or radiculose proximally. Leaves straight, not secund, more or less strongly and irregularly contorted or crisped with incurved apices when dry, the limb concave and erect-spreading to squarrose from an erect base when wet, narrowly to broadly oblong- or ovate-lanceolate or ligulate; apex acute to rounded-obtuse; margins involute-tubulose to plane or strongly recurved, rarely 2-stratose, distally irregularly and abruptly serrulate-dentate, with narrow, fragile decurrencies; apex acute to rounded-obtuse; costa narrow or broad, subpercurrent, sharply mammillose or densely covered with horned (columnar) papillae on both surfaces to nearly smooth, not rhizoidiferous, guide cells in 1 row, often individual cells in pairs, stereid bands 2 proximal to midleaf, adaxial band less developed, abaxial band strong, adaxial and abaxial epidermis distinct; all cells not pitted; medial laminal cells rounded-quadrate to short-rectangular, 1(-2) :1, sharply to bluntly mammillose on both surfaces or merely convex near apex, or densely covered with horned (columnar) papillae on both surfaces, sometimes 2-stratose near costa, walls evenly thickened; alar cells not differentiated in size or color; basal cells rectangular, 3(-5) :1. Specialized asexual reproduction occasional, by multicellular gemmae borne on branching stalks in leaf axils. Sexual condition autoicous or dioicous; perigonial buds below the perichaetium and sessile or terminal on male plants, perigonial leaves ovate, concave, short-acuminate; perichaetial leaves similar to distal cauline leaves. Seta single, yellow at first, becoming red-brown, 4-20 mm, erect. Capsule erect to weakly inclined, exserted, oblong-ovate, straight, arcuate to zygomorphic, with or without struma, smooth or irregularly furrowed-rugose when dry; operculum obliquely long-rostrate, usually as long as urn; basal membrane low, projecting above the mouth; peristome teeth 16, divided to the middle into 2 divisions, dark red, vertically pitted-striolate basally, papillose distally; annulus none. Calyptra cucullate, somewhat roughened at apex, covering capsule to just below the mouth. Spores 12-18(-20) µm, smooth or minutely papillose.[2] [more]

Dicranoweisia

Plants densely tufted, light to dark green, dull. Stems 0.5-3 cm, erect, forked, with central strand, with rhizoids confined to base of stems and firmly affixed to substratum. Leaves lanceolate, flexuose, crisped or curled when dry, 1-3.5 mm; costa single, subpercurrent, narrow; margins plane to incurved or recurved, 1- or 2-stratose; proximal cells elongate, 15-30 µm, smooth; alar cells with a few enlarged cells on margins, often colored or undifferentiated; distal cells subquadrate 7-10 µm wide, smooth or with longitudinal cuticular ridges. Specialized asexual reproduction sometimes present, multicellular, on abaxial surface, elliptic to short-linear, of 4-10 cells, 1-seriate or with occasional 2-seriate portions, smooth. Sexual condition autoicous; pergonial leaves abruptly narrowed to a long or short subula; perichaetial leaves variable, resembling vegetative leaves or broadly obtuse to acute or short-acuminate. Seta solitary, yellowish, 3-15 mm, smooth. Capsule light to dark brown when mature, elliptic to short-cylindric, 0.5-2 mm, smooth to longitudinally wrinkled when dry; annulus present, of 1-3 rows of cells, deciduous or absent; operculum rostrate, beak straight or oblique; peristome single, 16 teeth inserted below darkened cells of mouth, teeth entire to divided at apices, red-brown with hyaline tips. Calyptra cucullate, smooth, covering 1/3-1/2 of capsule, entire at base. Spores spherical, 15-20 µm, weakly papillose.[3] [more]

Holodontium

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Oncophorus

Plants erect, in loose to dense tufts, green to yellow-brown, glossy to somewhat dull. Stems 1-5(-8) cm, erect-spreading, simple or branching, radiculose proximally. Leaves lanceolate from an ovate base, gradually narrowed to abruptly subulate, crisped and curled when dry; margins plane or revolute, entire or often toothed at apex; costa strong, percurrent to slightly excurrent, narrow, with 2 stereid bands; distal laminal cells short-rectangular to subquadrate, smooth; basal laminal cells rectangular, elongate, smooth, alar cells poorly differentiated or sometimes slightly enlarged. Sexual condition autoicous; perichaetial leaves similar to the cauline; perigonia located below perichaetia. Seta 5-20(-22) mm, erect, twisted when dry, yellow to reddish yellow. Capsule inclined to horizontal, yellow-brown, arcuate, cylindric, urn 0.8-2 mm, constricted below the mouth, furrowed or smooth when dry, distinctively strumose; operculum rostrate, arcuate; peristome single, of 16 teeth divided halfway into two segments, vertically pitted-striolate proximally, papillose distally, red. Calyptra cucullate, smooth. Spores spheric, 14-25 µm, finely roughened, yellow to yellow-green.[4] [more]

Oreas

Oreoweisia

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Pseudohyophila

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Rhabdoweisia

Plants in short loose tufts, perennial, dull green to brownish. Stems 0.2-3 cm, erect, forked by innovations, red-brown, without central strand, rhizoids smooth, at base of stem. Leaves oblong-lanceolate to narrowly lanceolate, obtuse to acute, keeled, strongly divergent when moist, crisped to sinuose when dry, 2-4 mm; costa subpercurrent, formed of rectangular cells; margins usually recurved, mainly serrate to serrulate along distal margins, with 1-celled irregular teeth; laminal cells smooth, proximal cells hyaline to brownish, rectangular, thin-walled, absent chlorophyll; distal cells, quadrate to irregular, usually broader than long, chlorophyllose except for the marginal teeth. Specialized asexual reproduction absent. Sexual condition autoicous; perigonial leaves short-elliptic; perichaetial leaves not differing from the vegetative. Seta solitary, erect, yellow, 2-6 mm, smooth. Capsule exserted, erect, brown to yellow-brown, 0.5-1 mm, symmetric, ovoid to oblong-cylindric, when dry and empty contracted below mouth and deeply 8-furrowed,; annulus absent; stomata at base of urn, phaneropore; operculum obliquely subulate, 0.5-1 mm; peristome single, 16 teeth joined by a low basal membrane, inserted slightly below mouth, irregular and not forked, early deciduous. Calyptra cucullate, smooth, covering 1/2 of capsule. Spores nearly spherical to slightly angled, smooth, 16-20 µm, papillose.[5] [more]

Verrucidens

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More info about the Genus Verrucidens may be found here.

Bibliography

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Footnotes

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  1. Patricia M. Eckel "Cynodontium". in Flora of North America Vol. 27 Page 359, 376, 377, 378, 381, 383, 384, 425. Oxford University Press. Online at EFloras.org.
  2. Patricia M. Eckel "Dichodontium". in Flora of North America Vol. 27 Page 359, 377, 382, 383, 384, 585. Oxford University Press. Online at EFloras.org.
  3. Wilfred B. Schofield "Dicranoweisia". in Flora of North America Vol. 27 Page 17, 359, 376, 377, 395, 396, 421. Oxford University Press. Online at EFloras.org.
  4. Steven G. Newmaster "Oncophorus". in Flora of North America Vol. 27 Page 360, 377, 421, 423, 431. Oxford University Press. Online at EFloras.org.
  5. Wilfred B. Schofield "Rhabdoweisia". in Flora of North America Vol. 27 Page 359, 383, 428. Oxford University Press. Online at EFloras.org.

Sources

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Last Revised: August 24, 2012
2012/08/24 13:41:44