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Barbula fidelis

Interesting Facts

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Description

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Family Pottiaceae

Plants usually turf-forming or loosely cespitose, green distally and brown proximally. Stems 0.2-4(-10) cm, irregularly branching, mostly rounded-pentagonal but occasionally rounded-triangular in section , hyalodermis usually absent, sclerodermis sometimes present, central strand usually present, radiculose , occasionally bare or tomentose , axillary hairs several cells in length , sometimes the proximal 1-3 cells brownish. Stem leaves usually appressed and often contorted when dry, spreading when wet, ovoid to lanceolate or lingulate , often channeled or keeled , rarely concave , mostly ca. 1.5-3.5 mm; base usually ovate to oblong , occasionally sheathing the stem; margins usually recurved proximally, occasionally plane , incurved , or involute , entire or sometimes dentate distally, occasionally bordered by thick-walled or elongate cells or cells in one or more layers; apex rounded-obtuse to more commonly narrowly acute; costa ending a few cells before the apex to short-excurrent or long-excurrent as an awn , sometimes with photosynthetic outgrowths adaxially, adaxial cells quadrate or elongate in usually 2-4 rows , costa in medial transverse section usually with a differentiated epidermis adaxially or on both sides, 1 or 2 stereid bands , the abaxial stereid band usually rounded or reniform , guide cells in 1(-3) layers, hydroid strand occasionally present (sometimes multiple ) ; basal laminal cells usually differentiated, smooth or lightly papillose , rectangular, generally filling the base medially, sometimes rising marginally in a V shape , occasionally bulging, usually slightly wider than the distal laminal cells; distal laminal cells usually subquadrate , occasionally hexagonal or rarely short-rectangular or rhomboid , mostly small, ca. 9-16 mm wide, 1:1, papillae usually present over the distal laminal cells, solid or occasionally hollow, usually 2-fid but occasionally simple , sometimes flattened or compound , cell walls mostly evenly thickened, superficially flat to bulging, sometimes bulging only adaxially, usually in one layer. Specialized asexual reproduction common, by multicellular (rarely 1-cellular) gemmae borne on stalks in the leaf axils or more seldom on leaves, or by obovoid brood bodies borne on rhizoids in the soil, rarely by reduced or fragile leaves or fragile stems. Sexual condition dioicous or monoicous, occasionally rhizautoicous ; perigonia and perichaetia terminal or occasionally lateral on short branchlets . Perigoniate plants occasionally smaller than the perichaetiate, seldom nearly stemless and budlike. Perichaetial leaves often sheathing in the basal portion and then with elongate-rhomboid cells basally, usually larger than the cauline leaves, long-oval to long-lanceolate. Sporophytes often in transformation series of peristome reduction and seta shortening. Seta usually solitary, elongate, often twisted. Capsule stegocarpous or cleistocarpous , theca ovoid to cylindric , neck usually small or nearly absent; annulus little differentiated or of 1-2 rows of vesiculose cells, occasionally revoluble or deciduous in pieces ; operculum short-conic to short-rostrate, cells in straight or oblique rows; peristome teeth occasionally absent, more usually erect or twisted usually dextrose (counter clockwise ), yellow, orange, or red, rudimentary or consisting of 16 mostly twice cleft , spiculose, striate , or papillose, lanceolate teeth, or 32 linear , usually densely spiculose filiform divisions, the basal membrane usually low or absent, occasionally very high and trabeculate . Calyptra cucullate , smooth, occasionally mitrate, rarely papillose. Spores usually ca. 10-15 µm, occasionally much larger. Laminal KOH color reaction yellow to orange-red or red in 2% KOH solution.

Genera ca. 77, species ca. 1450 (40 genera, 165 species in the flora ) : worldwide, characteristic of harsh habitats .

This is the largest family of the mosses in number of genera. Its taxonomy is commonly considered difficult because of the obscure areolation , small size of the plants , and apparent phenotypic variation . A recent generic-level revision by R. H. Zander (1993) pulled together the scattered literature and de-emphasized sporophytic characters, allowing easier identification of sterile plants. The phylogenetic scheme adopted here approximates that of Zander (1993) as modified by Zander (2006) except that Gymnostomiella and Luisierella are moved from the Barbuloideae to the Pottioideae, in part for convenience in identification. The large number of anatomical characters available permits better identification of previously poorly understood taxa. The color tests refer to the reaction of the cell walls of the distal laminal areolation to 2% potassium hydroxide solution, which may require examination under the compound microscope for determination. Sectioning of leaf and stem is necessary and is described by Zander (1993) . A twisted peristome, strongly differentiated costal anatomy , and the complexly papillose distal laminal cells are characteristic of this mostly acrocarpous family, commonly found in harsh environments.[1]

Genus Barbula

Plants loosely cespitose or forming cushions , yellowish brown, brown or blackish distally, yellowish brown to reddish brown proximally. Stems short to elongate , to 2(-3.5) cm; hyalodermis rarely present, sclerodermis present, central strand present; axillary hairs short to elongate, all cells almost always hyaline . Leaves appressed incurved to weakly spreading , often contorted or twisted about stem, occasionally catenulate when dry, spreading when moist; ligulate or broadly lanceolate to long-triangular, adaxial surface usually deeply grooved along costa, occasionally broadly concave ; base weakly differentiated to broadened and somewhat sheathing , proximal margins sometimes narrowly decurrent; margins usually recurved in proximal 1/2-2/3, occasionally plane throughout, entire or occasionally weakly denticulate near apex; lamina 1-stratose; apex rounded to obtusely acute, usually mucronate , occasionally entire or apiculate ; costa percurrent to shortly excurrent as a sharp mucro , occasionally ending a few cells before the apex, adaxial outgrowths absent, adaxial cells elongate, occasionally quadrate to short-rectangular, in 2-3(-5) rows ; transverse section ovate to semicircular, adaxial epidermis differentiated, adaxial stereid band usually present, usually small, guide cells 2-4 in 1 layer, hydroid strand occasionally present, abaxial stereid band present, usually strong , semi-lunar in sectional shape , abaxial epidermis usually present but weakly differentiated; basal cells differentiated across leaf or reaching higher medially or occasionally marginally, rectangular, usually little wider than the distal cells, 3-5:1, walls of proximal cells thin to evenly thickened; distal medial cells quadrate, usually 1:1, 1-stratose; papillae hollow or solid, multiplex to 2-fid, 2-3 per lumen , occasionally simple or absent, cell walls thin to evenly thickened, superficially bulging on both free sides. Specialized asexual reproduction by tubers borne on proximal rhizoids or gemmae borne on axillary stalks . Sexual condition dioicous or possibly sometimes rhizautoicous . Perichaetia terminal , interior leaves sometimes strongly sheathing, little differentiated or ovate to long-lanceolate, laminal cells usually rhomboid in proximal 1/2-3/4. Seta 0.5-2.5 cm. Capsule stegocarpous , theca ovate to long-cylindric, annulus weakly differentiated to strong, of 1-3 rows of vesiculose cells, sometimes revoluble or deciduous in pieces ; operculum usually long-conic; peristome teeth of 32 narrow rami, filamentous to narrowly triangular, usually strongly twisted counterclockwise . Calyptra cucullate . Spores mostly 8-12 µm. KOH laminal color reaction yellow, occasionally yellowish orange.

Species ca. 200: worldwide in temperate zones.

Barbula has been much reduced in size. K . Saito (1975) presented cogent reasons for recognizing Didymodon as distinct . Characters of importance in distinguishing Barbula are: axillary hairs almost always entirely of hyaline cells; leaf adaxially usually deeply grooved along the costa; distal laminal cell papillae rough, knobby, obscuring the lumens, and protuberant along the distal laminal margins; costa usually excurrent as a sharp mucro or an apiculus of one or more clear cells; peristome is long and twisted, and as Saito (1975) pointed out, Barbula has gemmae generally larger than those of Didymodon. The three sections are represented in the flora area: sect. Barbula, including B . unguiculata and B. orizabensis; sect. Convolutae Bruch & Schimper (Streblotrichum P. Beauvois), including B. amplexifolia, B. convoluta, and B. indica; and sect. Hydrogonium (Müller Hal.) K. Saito [Hydrogonium (Müller Hal.) K. Saito [Hydrogonium (Müller Hal.) A. Jaeger], including B. bolleana. For many taxa previously long-held in Barbula, see 16. Didymodon.[2]

Taxonomy

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Notes

Name Status: Accepted Name .

Last scrutiny: 19-Jul-2004

Similar Species

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Members of the genus Barbula

ZipcodeZoo has pages for 10 species, subspecies, varieties, forms, and cultivars in this genus:

B. agraria (Barbula Moss) · B. amplexifolia (Barbula Moss) · B. convoluta (Convoluted Barbula Moss) · B. coreensis (Barbula Moss) · B. ehrenbergii (Ehrenberg's Barbula Moss) · B. eustegia (Barbula Moss) · B. indica (Barbula Moss) · B. indica var. indica (Barbula Moss) · B. unguiculata (Barbula Moss) · B. wollei (Bartramia Moss)

More Info

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Further Reading

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Notes

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Contributors

Identifiers

Footnotes

  1. Richard H. Zander "Pottiaceae". in Flora of North America Vol. 27 Page 5, 12, 13, 110, 163, 265, 286, 377, 381, 468, 476, 482, 491, 548, 562, 56. Oxford University Press. Online at EFloras.org. [back]
  2. Richard H. Zander "Barbula". in Flora of North America Vol. 27 Page 15, 38, 479, 492, 525, 527, 528, 529, 540, 566, 577, 606, 610. Oxford University Press. Online at EFloras.org. [back]
Last Revised: 7/20/2012