BFNA Title: Dendroalsia
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.
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