Bryolawtonia vancouveriensis, Bryologist 93: 328–331. 1990. -- Bestia vancouveriensis (Kindb.) Wijk & Marg., Taxon 10: 24. 1906. -- Thamnium vancouveriensis Kindb. in Mac., Bull. Torr. Bot. Club 17: 277. 1890.

   Plants in dense mats or cushions, glossy dark-green to olive or brownish-green, pinnately branched and often with flagelliform and caducous branchlets. Primary stems short and prostrate with secondary stems (stipes) to 3 cm long, decumbent to ascending. Leaves to 1.0 mm, 2–4: 1, complanate; not plicate, oblong-ovate, sometimes contracted at the middle into a ligulate distal portion, rounded to obtuse at apex, imbricate when dry and little changed when moist; laterally inserted leaves asymmetric with their postical margins broadly incurved at base,. Margins plane, at base somewhat cordate but not decurrent, serrulate to serrate above the middle, sometimes serrulate throughout. Median cells smooth, 6–9 µm wide, 2–5: 1, thick-walled with lumen/wall ratio to 1: 1, but not pitted. Alar cells quadrate to transversely elongate in a small group up to 10 cells in each dimension, thick-walled, grading into laminal cells. Apical cells rhomboidal, nearly isodiametric. Costa extending about 1/2 to 3/4, often forked distally. Pseudoparaphyllia deltoid to orbicular, strongly overarching the bud. Axillary hairs 2–3 celled, to 100 µm with one basal brown cell, not offset from leaf insertion. Rhizoids red-brown, 6–8 µm, smooth, inserted on stem immediately below abaxial costal insertion.

   Dioicous with male plants smaller than females. Perigonia on main axis or terminal on short lateral branches. Perichaetia on main axis, to 3 mm long in an acicular cluster, strongly convolute around the seta. Perichaetial bracts ecostate or with a narrow costa present only near leaf middle, abruptly acuminate from a ligulate-lanceolate base, cells long rectangular, to 25: 1. Seta 5–10 mm long, short-exserted. Capsule brown, curved and inclined, not distorted or sulcate when dry, somewhat strangulate at mouth. Urn to 1.8 mm, about 2–3: 1. Exothecial cells 1–3: 1, 12–18 µm wide, thick-walled with a lumen/wall ratio about 3: 1, stomata restricted to neck. Operculum short-rostrate, about 1/2 as long as urn. Exostome horizontally striate below, becoming low papillose above, red-brown. Endostome segments lightly papillose, open on keel, narrow, about as long as exostome with basal membrane about 1/4 of total length. Cilia 2, well-developed. Spores low papillose, 12–15 µm.

Vouchers: Alameda Co.: Strawberry Canyon about 0.5 mile above UC Botanic Garden, Norris 82610; Del Norte Co.: Damnation Creek Trail, Del Norte Redwoods State Park, Norris & Taranto 10978 & 10980; Humboldt Co.: Cathedral Trees Trail, Prairie Creek Redwoods State Park, Jamieson 872 (UC); Lake Co.: Grizzly Canyon between Elk Mountain and Horse Mountain, Mendocino National Forest, Toren 7685 (CAS); Marin Co.: trail near Mud Lake, Point Reyes National Seashore, Norris 71809; Mendocino Co.: near Ranger Station, Sinkyone Wilderness State Park, Norris 71753 and North Coast Range Preserve about 11 km north of Branscomb, Bourell 1610 (CAS) [determined by Toren]; San Francisco Co.: Golden Heights Park, Shevock 19202 & Toren 7943 (CAS); Santa Cruz Co.: Spring Trail, Pogonip Park near UC Santa Cruz, Kellman 316 (UC).

Literature: Kellman 2003; Norris and Enroth 1990; Shevock and Toren 2001. As Bestia holzingeri Koch 1950a; Koch and Ikenberry 1954. As Bestia occidentalis Koch 1950a. As Bestia vancouveriensis Harthill et al. 1979; Holmberg 1969; Jamieson 1969; Lawton 1971; McCleary 1972; Yurky 1990. As Thamnium holzingeri Howe 1896. As Porotrichum vancouveriense Crum 1987; Yurky 1995.

Illustration References: Malcolm et al. 2009 p. 306; Lawton 1971. As Thamnium holzingeri Renauld and Cardot 1894.

Elevation by latitude plot for Bryolawtonia vancouveriensis
   in California