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BFNA Title: Dendroalsia |
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Dendroalsia
- Cryphaeaceae XX. DENDROALSIA E. Britton in Brotherus,
Nat. Pfl. 1(3): 859. 1906 * [Greek
dendros, tree, plus the generic name Alsia, suggesting a dendroid
Alsia] Clayton
C. Newberry Plants
in thick loose mats. Secondary stems erect-ascending,
densely foliate. Paraphyllia abundant. Leaves
broadly ovate to ovate-lanceolate, distinctly
5-ranked along the stem. Sexual condition dioicous. Seta
longer than the perichaetial leaves. Capsule
rarely exceeding 2.5 mm; stomata mostly basal, phaneroporus;
annulus 2-seriate, evanescent; peristome double;
endostome segments arising from a low basal membrane; operculum
conic-rostrate to oblique-rostrate. Calyptra cucullate,
naked. Species 1, varieties none: western The characterization of Dendroalsia as given by D. H. Norris
and J. R. Shevock (2004) is accurate and
descriptive: “Dendroalsia is especially easy to recognize when the plant is dry---each of
the branches curls downward so that the entire branched system resembles a
clenched fist, with its curved fingers representing the branches.” When wet, the stems and branches uncurl to
form broad, handsome fern-like tails orthotropic to the substrate (usually a
tree trunk or vertical rock face). SELECTED REFERENCES Norris, D. H. and J. R. Shevock. 2004. Contributions towards a bryoflora
of California II. A key to the mosses. Madroño 51:
133--269. Manuel, M. 1974. A revised classification of the Leucodontaceae and a revision of the subfamily Alsioideae. Bryologist
77: 531--550. 1.
Dendroalsia abietina (Hooker) Neckera abietina Hooker,
Musci Exotici 1: 7. 1818 Plants
robust or unusually large, stiff, wiry and dark green to green when dry,
softer and bright green when moist, tail-forming. Primary
stems to 10--15 cm, plagiotropic, tightly
adhering to the substrate, stoloniform, densely
rhizoidal. Secondary stems usually 10--12(--25) cm, circinate
and curling downward when dry, opening and orthotropic when moist, proximally
stipitate, distally pinnate to 2-pinnate branching and
frondiform, more rarely nearly dendroid;
internal cells almost all incrassate, the cortical cells particularly so,
these 12--18 cells thick and darkly pigmented, ± grading into slightly
larger, less pigmented and less incrassate medullary
cells; central strand lacking; paraphyllia and
rhizoids both abundant throughout the stem, the paraphyllia
multiform, 1- to multiseriate to narrowly subulate,
often branching; pseudoparaphyllia investing the
branch buds, subulate to deltate to subfoliose, irregularly dentate. Lateral
or tertiary branches common, ± equal, to 30 mm, often bearing even
smaller (less than 10 mm) quaternary branchlets;
internal anatomy similar to that of main stem, only smaller, the cells less
pigmented and less incrassate, the cortex 4-6 cells thick. Stem
leaves 2--3 x 1--1.5 mm, erect to erect-patent when dry, spreading when
moist, concave, ± plicate; leaf apex acute to acuminate, the apical cells isodiametric to oval-rhombic, incrassate, often prorate; median
cells more linear, 10-25 × 5-6 µm, incrassate, occasionally prorate; leaf base
slightly decurrent, the basal cells incrassate, roughly
isodiametric, filling the basal angle of the
leaves; margin recurved and entire at the base,
usually increasingly plane and dentate towards the apex; costa
strong, subpercurrent to percurrent
to barely excurrent, occasionally sinuous,
increasingly dentate distally. Branch leaves similar to main stem
leaves but usually smaller and narrower, 1.5-2 × 1 mm. Perigonia common
along the frondose portions of the secondary stem,
occasional on the tertiary and even the quaternary branchlets,
to 2 mm; perigonial leaves smallish, deltoid-apiculate to lanceolate-apiculate,
the cells prorate, the margin increasingly serrate distally, the median
margin revolute; antheridia to 1 mm, fusiform. Perichaetia borne ventrally mostly on the secondary stem,
occasionally on the tertiary stems; perichaetial
leaves grading from short-deltoid to deltoid-apiculate
or longer, sheathing, truncate-apiculate, to 2.5
mm, the basal cells thin-walled, rectangular at 4-5:1, the median and distal
cells incrassate, elongate at 3-6:1. Seta brown, short, 0.7-2 (-3) mm,
straight. Capsule brown to red-brown, 2-2.5 × 1 mm, barely exserted,
erect-symmetric, oblong-ovoid to ovoid, plicate when dry, the surface smooth;
operculum conic-rostrate; exostome teeth 16, white, to 0.6 mm,
linear-subulate, trabeculate, coarsely papillose distally, less so proximally;
endostome segments white, slender, as long as the exostome teeth, narrowly
subulate, slightly carinate, strongly papillose,
persistent, basally fused; cilia lacking.
Spores spherical, pale
brown, papillose, 15-25 \um. Often widely spreading, covering whole trunks, limbs and
branches of trees, or large surfaces of rocks; 0--1000(--2000) m: B.C.; Dendroalsia abietina is
an important component of the bryoflora of far
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