Orthotrichum speciosum

   Plants erect in olive-green to brownish-green tufts, to 5 cm high. Leaves erect-spreading when moist but, when dry, appressed with apices recurved. Leaves to 3.5 mm long, 4.5–6: 1, lanceolate to narrowly lanceolate with narrowly acute to acuminate apices. Median laminal cells quadrate to short elliptic with rounded lumens, thick walled with strong corner thickening, to 12 µm wide, with 1–3 inconspicuous papillae on both surfaces. Basal juxtacostal cells rectangular, 3–6: 1, to 14 µm wide with lateral walls sinuose and unevenly thickened. Basal marginal cells isodiametric and papillose, similar to median laminal cells. Margins recurved but not revolute from base to near the apex, entire. Costa ending at the base of the acumen, not prominently keeled. Costa cross-section nearly terete and homogeneous, at mid-leaf only 3 cells thick with only 2 cells in the adaxial layer, 1 cells in the median layer and 4–5 cells in the abaxial layer. Axillary hairs with one basal light brown cell, not offset from leaf insertion; centrally inserted ones to 6 cells and 200 µm long, but laterally inserted ones only 3 cells long (80 µm). Rhizoids present and sometimes abundant near base of plant but mostly sparse on distal portions of plant, smooth, red-brown, to 20 µm in diameter at base, sparingly branched. Stem cross-section rounded pentagonal without a central strand, with hyaline inner corticals and with 1–2 layers of pachydermous, red brown outer cortical cells.

   Autoicous with perigonia in leaf axils near the perichaetia or on the apices of separate short branches. Perichaetial bracts similar to, but smaller than the vegetative leaves. Capsule at least somewhat emergent on a yellow to yellow-brown, smooth and erect seta of about 2.5 mm in length. Urn poorly differentiated from the long and ribbed neck, yellow-brown when fresh, to 3 mm long, 3.5–5: 1, erect, lightly sulcate in distal portion with eight low ribs, not at all strangulate. Operculum short rostrate. Annulus well-defined, falling in fragments. Exothecial cells at capsule mouth differentiated in up to 3 rows, to 25 µm broad, isodiametric to transversely elongate with rounded lumens. Exothecial cells at middle of urn rectangular, 4–6: 1, to 30 µm broad, thick walled with lumen: wall ratio about 1: 1, not much differentiated between the valleys and the ridges of the sulcate capsule. Exothecial cells, in cross-section, with very thick outer walls but with thin and collapsed inner walls. Stomata present on proximal 1/2 of urn, phaneroporous. Exostome teeth reflexed against capsule wall when dry, fused in pairs and appearing to be only 8 in number, pale-brown, to 250 µm long, papillose to papillose-reticulate. Endostome segments 8, about as long as the exostome, lightly papillose, formed of 2 rows of cells throughout most of their length. Calyptra campanulate and plicate, with cells lacking papillae or prorae, sparsely to densely clothed with multiseriate and prorate-papillose and sparingly papillose hairs. Spores green, to 22 µm, coarsely papillose.

Vouchers: Del Norte Co.: Doctor Rock, Six Rivers National Forest, Norris 57683; El Dorado Co.: South Fork American River at Carpenter Creek, Eldorado National Forest, Norris 58427; Marin Co.: Inverness Ridge Trail near Limantour Road, Point Reyes National Seashore, Yurky 337 (SFSU); Nevada Co.: Red Mountain on trail from Indian Springs, Tahoe National Forest, Norris 102615; Shasta Co.: Soda Creek Road about 3 miles northeast of Interstate 5 near Dunsmuir, Shasta-Trinity National Forest, Norris 84773; Siskiyou Co.: Six Mile Creek between Callahan and Cecilville, Klamath National Forest, Norris 22964; Tulare Co.: East Fork Kaweah River below Atwell Mills Campground, Sequoia National Park, Norris 46493

Literature: Harthill et al. 1979; Koch 1950a; Lawton 1971; Lesquereux 1868; McCleary 1972; McGrew 1976; Sayre 1940; Watson 1880; Yurky 1990.

Illustration References: Ignatov and Ignatova 2003; Ignatov and Lewinsky-Haapasaari 1994; Ireland 1982; Lawton 1971; Vitt 1973; Vitt and Darigo 1997.

Elevation by latitude plot for Orthotrichum speciosum
   in California