Grimmia laevigata (Bridel) Bridel, Bryol. Univ. 1: 183. 1826.
Campylopus laevigatus. Bridel. Musc. Recent. Suppl. 4: 76. 1819.
Grimmia campestris Burchell ex Hooker. Musci Exot. 2: 129. 1819.
Bryol. Univ. 183. 1826. -- Campylopus laevigatus Brid., Musci Rec. Suppl. 4: 76. 1819.
Grimmia campestris Burchell ex Hook., Musci Exot. 2: 129. 1819.
Grimmia leucophaea Grev., Mem. Wernerian Nat. Hist. Soc. 4: 87. 1822.
Grimmia sarcocalyx Kindb. in Mac., Cat. Can. Pl. 6: 66. 1892.
Plants to 1.5 cm high, in hoary green to gray-green cushions, opaque-green to nearly black below. Leaves loosely imbricate when dry, loosely erect-spreading when moist, somewhat concave but not at all keeled, to 3 mm long with the awn constituting nearly 1/2 of that length, ovate-lanceolate from a loosely sheathing somewhat expanded base, 2.5–3.5: 1. Median leaf cells in regular longitudinal rows, unistratose in the expanded base but uniformly bistratose in the limb, smooth, to 7 µm wide, isodiametric with lumens irregular but without corner thickenings. Marginal cells not differentiated. Basal juxtacostal cells elliptical, to 3: 1, to 15 µm wide, with irregularly thickened lateral walls. Basal marginal cells transversely elongate, 0.5–0.7: 1, to 15 µm wide. Costa flared at the base and filling 1/3–1/4 of immediate leaf base, narrowed and obscure above, percurrent in the somewhat acuminate awn. Costa cross-section at leaf middle broad and flattened, less than 1.5 times as thick as the adjacent leaf, with a weak abaxial band of stereids or substereids and with a single layer of larger cells on the adaxial face. Margin of leaf limb plane to incurved, entire below. Awn strongly decurrent with its margin somewht serrulate, and with its surface spinose-prorate. Axillary hairs to 100 µm long, with 6–8 nearly isodiametric and thick- walled cells, without a basal brown cell. Rhizoids red brown, to 15 µm wide at base, smooth. Stem cross-section rounded-triangular with a large and well-defined central strand, and with leptodermous, hyaline and large inner cortical cells, and with the 1–2 cell-thick outer stereome composed of much smaller, thick-walled cells strongly pigment with yellow to yellow-brown.
Dioicous with male and female plants similar. Perichaetial leaves loosely sheathing base of seta, somewhat larger and with a relatively longer, less decurrent awn than the adjacent vegetative leaves. Seta to 2.5 mm long, yellow to pale brown, straight and smooth. Urn erect, symmetrical, smooth to lightly wrinkled when dry, to 1.2 mm long, 1.5–2: 1, not strumose. Operculum short rostrate, about 1/3 as long as urn. Annulus formed of 2–3 rows of relatively more thin-walled cells. Calyptra mitrate, covering about 1/2 of urn. Peristome red-brown, to 200 µm long, cribrose along median line near the apex, papillose to vertically striate-papillose. Exothecial cells to 25 µm wide, not in regular vertical rows, quite irregular in size and shape, rectangular 2–4: 1, rather thick walled. Stomata phaneroporous, restricted to base of urn. Spores smooth, to 12 µm.
|Literature||Albert 1988; Crum and Anderson 1981; Flowers 1973; Harpel 1980a; Harthill et al. 1979; Holmberg 1969; Kellman 2003; Koch 1950a, 1951e; Koch and Ikenberry 1954; Lawton 1971; Long 1978; McCleary 1972; Mishler 1978; Sayre 1940; Shevock and Toren 2001; Toren 1977; Whittemore and Sommers 1999; Yurky 1990, 1995. As Grimmia leucophaea Kingman 1912; Lesquereux 1868; Lesquereux and James 1884; Watson 1880.|
|Illustrations||Malcolm et al. 2009 p. 64; Crum and Anderson 1981; Flowers 1973; Greven 2003; Ignatov and Cao 1994; Ignatov and Ignatova 2003; Lawton 1971; Muñoz 1999a; Sharp et al. 1994; Smith 1978.|
|Bioregions||CaR, CW, DMoj, DSon, NW, SN, SW.|
|Vouchers||Butte Co.: North Table Mountain, Cherokee Road, Janeway 5569 (MO) [determined by Muñoz]; Fresno Co.: Cripe Road near Patterson Road, Sierra National Forest, Shevock & York 14940 (determined by Muñoz); Kern Co.: Piute Mountain Road, BLM Bodfish Piute Cypress Natural Area, Piute Mountains, Shevock 12476; Riverside Co.: Highway 74 at milepost 76.50 near Santa Rosa Mountain Road, San Jacinto Mountains, San Bernardino National Forest, Shevock 20519; San Diego Co.: Matagual Creek, Volcan Mountains, Stark 594 (MO) [determined by Muñoz]; San Mateo Co.: Edgewood Park, Old Stage Road, Whittemore 5276 (MO) [determined by Muñoz]; Santa Barbara Co.: Cherry Canyon, Santa Rosa Island, Channel Islands National Park, Shevock 20908 (confirmed by Muñoz).|