Orthotrichum hainesiae Austin; O. kingianum Lesquereux; O. laevigatum var. kingianum (Lesquereux) Grout; O. lonchothecium Macoun & Kindberg; O. macounii Austin; O. macounii var. lonchothecium (Macoun & Kindberg) Grout; O. raui Austin; O. roellii Venturi; O. roellii subsp. schlotthaueri (Venturi) Kindberg; O. roellii subsp. stenocarpum (Venturi) Kindberg; O. schlotthaueri Venturi; O. speciosum var. brevicaule Lesquereux; O. speciosum var. hainesiae (Austin) Paris; O. speciosum subsp. laevigatum (J. E. Zetterstedt) J. J. Amann; O. speciosum var. polyanthum Lesquereux; O. speciosum var. polycarpum Lesquereux & James; O. speciosum var. raui (Austin) Lesquereux & James

Plants (0.5-)2(-4.3) cm, . Stem leaves stiff, erect-appressed, slightly secund when dry, oblong-lanceolate, lanceolate, or ovate-lanceolate, 2-4.3 mm; margins revolute from base to near apex, entire; apex obtuse, bluntly or narrowly acute, or gradually acuminate; basal laminal cells rectangular to elongate, grading to elliptic-quadrate, walls thick, nodose; distal cells 8-12 µm, 1-stratose, papillae 1-3 per cell, conic or 2-fid, lo w. Specialized asexual reproduction absent. Sexual condition gonioautoicous. Seta 1.5-4 mm. Capsule fully exserted, cylindric, 1.4-2.6 mm, smooth or sometimes slightly plicate distally; ; stomata superficial; peristome double; prostome absent or rudimentary; exostome teeth 16, erect, papillose; endostome segments 8, occasionally rudimentary, , of 1 row of cells, smooth. Calyptra conic-oblong, smooth, sparsely hairy, hairs finely papillose. Spores 10-15 µm.

Non-calcareous boulders in mesic, open coniferous forests, base of deciduous trees; moderate to high elevations (500-3000 m); Alta., B.C., Man., N.W.T., Sask., Yukon; Alaska, Ariz., Calif., Colo., Idaho, Mont., Nev., Oreg., S.Dak., Utah, Wash., Wyo.; Europe; e Asia (Japan).

Orthotrichum laevigatum is part of a complex group of intergrading taxa that generally are characterized by exserted, cylindric capsules with 16 erect or reflexed exostome teeth and a poorly developed endostome. Gametophytically, robust plants have stiff, erect leaves and large, blunt papillae. This complex is treated here as three species: O. holzingeri, a distinct, highly specialized species of seasonally wet rock with smooth exostome teeth, smooth laminal cells, smooth calyptra, and slightly ribbed capsule as distinguishing features; O. laevigatum, distinguished by smooth capsule and erect, papillose exostome teeth; and O. pylaisii, distinguished by slightly 8-ribbed capsule and reflexed-recurved exostome teeth.