BFNA Title: Alsia
Author: C. C. Newberry 
Date: February 25, 2008
Edit Level: R
Version: 3

Bryophyte Flora of North America, Provisional Publication
Missouri Botanical Garden

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XX. ALSIA Sullivant, Proc. Am. Ac. Arts Sci. 3: 184. 1855 *  [Anagram of the generic name Lasia, reflecting overall similarity to Lasia now Forsstroemia]

Clayton C. Newberry


Secondary stems erect-ascending, densely foliate.  Branching pinnate and frondiform distally.  Paraphyllia abundant, 1-seriate-filiform to dissected-lanceolate and irregularly branching; pseudoparaphyllia investing the branch buds, dissected-lanceolate to subfoliose. Stem leaves   loosely imbricate when dry, spreading when moist, concave, lanceolate to oblong-lanceolate; margins slightly recurved, mostly entire, at the apex plane and sometimes weakly serrulate, at the base more strongly recurved; apex acute to acuminate, the base obtuse; costa variable even on the same plant, either weak and almost absent, or short and double, or strong and disappearing halfway up the leaf;  apical cells short, oval-rhombic, incrassate; median cells oval-oblong, 2--3:1, incrassate; basal cells rounded to quadrate, incrassate, filling the basal angles and extending halfway up the margin; all marginal cells shorter than laminal. Branch leaves smaller than main stem leaves, narrower, the costa weaker or sometimes altogether lacking.  Sexual condition dioicous.  Seta usually shorter than the perichaetial leaves, 3--5 mm.  Capsule short, erect-symmetric or nearly so; stomata sunken and mostly basal; annulus not differentiated; peristome double; endostome segments arising from a narrow basal membrane; operculum oblique-rostrate.  Calyptra cucullate, naked. Spores brownish, finely papillose, to 20 \um.


Species 1, varieties none:  maritime Pacific coast of western North America.


Alsia is strikingly similar to Forsstroemia trichomitria, but the two species are completely distinct geographically.  Alsia is endemic to the west coast of North America, while F. trichomitria is broadly distributed in eastern North America, occurring no further west than Oklahoma.  The stems of Alsia are densely invested with paraphyllia, while paraphyllia are lacking in F. trichomitria.


SELECTED REFERENCES  Norris, D. H. and J. S. Shevock.  2004.  Contributions towards a bryoflora of California II.  A key to the mosses.  Madroño 51(2): 133--269.  Manuel, M.  1974.  A revised classification of the Leucodontaceae and a revision of the subfamily Alsioideae.  Bryologist 77: 531--550. Schofield, W. B. 1976.  Bryophytes of British Columbia III:  habitat and distributional information for selected mosses.  Syesis 9: 317--354.


1. Alsia californica (Hooker & Arnott) Sullivant, Proc. Am. Ac. Arts Sci. 3: 185. 1855


Neckera californica Hooker & Arnott, Bot. Capt. Beechey’s Voyage, 162.  1833


Plants robust, green to yellow-green to stramineous, in thick, loose mats, tail-forming and spreading widely over the substrate.  Main stem inconspicuous, stoloniform, plagiotropic, tightly adnate against the substrate.  Secondary stems to 8 cm, irregularly subpinnate proximally, more regularly pinnate and frondiform-complanate distally, often curling upward when dry, uncurling erect-ascending when moist, internally divided into a strong 4--6-layered cortex of incrassate, yellow to light brown cells and a medulla of loose, thin-walled hyaline cells; central strand lacking.  Stem leaves to 2 mm.  Lateral branches of unequal length, 5--6(--15) mm, occasionally bearing gametangia or small (less than 3 mm) branchlets, occasionally flagelliform and tapering in moist maritime situations; branch paraphyllia similar to those on main stem, less common. Perigonia conspicuous, persistent, barely 1 mm, borne ± subpinnate and complanate on the secondary stem, occasionally on the side branches, the leaves smallish and apically apiculate, mostly ecostate, the antheridia fusiform.  Perichaetial branches distinctive, borne ± irregularly subpinnate and complanate on the main stem, up to 5 mm; the outer perichaetial leaves ovate to ovate-lanceolate, ecostate, the inner elongate, sheathing, at the apex narrowing abruptly and contracted into a filiform-acuminate point, laminal cells elongate, basally rectangular at 1:5, towards mid-leaf to 1:16.  Seta brown to red-yellow, straight, mostly sheathed by and only slightly emergent from the perichaetial leaves.  Capsules yellowish brown, 1.5--2 mm, barely exserted beyond the perichaetial leaves, oblong-cylindric, the surface smooth; exostome teeth hyaline to brownish yellow, broadly subulate, trabeculate, punctulate-scabrous; endostome segments pale brownish yellow, narrowly subulate, occasionally perforate up the middle, finely papillose; basal membrane low; cilia lacking. 


Bark of trunks and branches of Acer, Alnus, Chrysolepis, Lithocarpus, Quercus, Picea, Populus, Sambucus, Sequoia, Umbellularia; rock surfaces, usually siliceous, north of California occasionally calcareous; 0--700 m (usually less than 100 m); B.C.; Calif., Oreg., Wash.; Mexico (Baja California).


Alsia californica is an important component of the moss flora of mostly maritime western North America.  In California it extends primarily from Los Angeles County to Del Norte County.  It diminishes in frequency roughly at the California-Oregon state line, continues sporadically northward along the coast, and then reappears more commonly in Puget Sound, Vancouver Island and southwest British Columbia.  Literature reviews fail to produce verifiable reports, and herbarium searches fail to produce reliable collections, of A. californica anywhere north of the 50th parallel (central Vancouver Island); the two mid-nineteenth-century reports of its occurrence in Alaska are probably mislabeled.  In California, Oregon and Washington it usually grows in maritime habitats, quickly diminishing with distance from the coast and penetrating inland only in canyon riparian microhabitats (Norris and Shevock, 2004).  In British Columbia, it extends further inland, up the Fraser River Valley approximately 150 km to just east of Hope (W. B. Schofield 1976).  Ecovariant forms occur on guano-enriched rock islands immediately offshore throughout its range.  Flagelliform variants, with ecostate, caducous leaves and/or fewer paraphyllia, occur in poplar stands of the Fraser Valley and occasionally in the sun-drenched upper canopies of coastal redwoods.