Didymodon brachyphyllus (Sullivant) Zander. Phytologia 41: 24. 1978.
Plant erect, green to dark green, usually with a reddish blush. Stems to 5 cm tall, erect-spreading when dry, not at all keeled. Leaves ovate to ovate-lanceolate, smallest near base, gradually larger above but uniform in shape throughout. Leaves appressed when dry; weakly spreading when moist. Leaves not keeled, only narrowly channeled along costa in distal region; broadly concave in at least the proximal ½, about 1 mm long and 0.4 mm wide, margins recurved from near the base to at least ¾ up the leaf with margins entire. Costa smooth and dark, with obvious boundaries except near apex where there may be short spurs, with elongate cells in 4–6 rows on dorsal face, percurrent or nearly so in the cucullate and blunt apex. Costa cross-section elliptical, about 1.2: 1, with differentiated abaxial and adaxial epidermises, with a group of 5–8 guide cells and with mostly a single abaxial stereid band. Median laminal cells isodiametric, to 12 m in diameter, rather thin-walled without corner thickenings and with rounded lumens, nearly smooth but with a few low papillae over the lumen, especially in distal, marginal portion of leaf. Basal laminal cells mostly similar to median cells or somewhat more elongate-rectangular, 1–2.5: 1, mostly smooth, with longitudinal and transverse walls with lumen: wall ratio about 2–3: 1. Stem round in cross-section, with one layer of brown and thick-walled cortical cells surrounding a hyaline and thin-walled central area with a central strand. Rhizoids red-brown and smooth, to 10 m at insertion, scattered on stem adaxial to leaf insertion. Axillary hairs 4–6 cells in length with 2 basal brown cells; these isodiametric and uniseriate and evenly cylindric, to 120 m long, with diameter about 12 m, not expanded distally or proximally.
Dioicous. Seta yellow but reddened with age, to 12 mm long. Calyptra cucullate, smooth and glabrous. Capsule stegocarpous, to 1.2 mm long, erect and evenly cylindric with operculum rostrate. only a little shorter than urn. Exothecial cells to 25 µm broad, 2–3: 1. Peristome to 0.5 mm long, not twisted or only slightly so twisted formed of 16 separate filiform hyaline teeth ornamented throughout their length by closely placed processes. Spores hyaline to light brown, spherical, about 15 m in diameter, smooth.
|Literature||Kellman 2003. As Barbula brachyphylla Harpel 1980a; Harthill et al. 1979; Koch 1950a; Koch and Ikenberry 1954; Lawton 1971; Lesquereux 1868; Lesquereux and James 1884; Long 1978; McCleary 1972; Mishler 1978; Sayre 1940; Spjut 1971; Steere 1954; Steere et al. 1954; Sullivant 1856; Toren 1977; Watson 1880; Yurky 1990. As Didymodon vinealis var. brachyphyllus Yurky 1995.|
|Illustrations||Malcolm et al. 2009 p. 124; Lawton 1971; Mogensen and Zander 1999; Sharp et al. 1994; Zander and Ochyra 2001.|
|Bioregions||CW, NW, SN, SNE, SW.|
|Vouchers||Contra Costa Co.: Vasco Caves Preserve, East Bay Regional Parks, Shevock, O'Brien, & Jessup 15025 (determined by Zander); Lake Co.: Highway 20 about 10 miles east of Highway 53 junction, Toren & Dearing 7317 (CAS) [confirmed by Zander]; Marin Co.: Shell Beach Trail, Yurky 325 (SFSU); Riverside Co.: Garnet Queen Creek, Santa Rosa Mountains, Harpel 2355 (pers. herb.); San Diego Co.: French Creek, Palomar Mountains, Stark 771 (MO); Tulare Co.: Highway 190 at Soda Creek near Moorehouse, Sequoia National Forest, Shevock 15650 (determined by Zander); Ventura Co.: San Nicolas Island, Weber & Bratt 100684 (MO).|