Ulota obtusiuscula -- Ulota alaskana Card. & Ther., Proc. Wash. Acad. Sci. 4: 309. 1902. -- Ulota crispa var. alaskana (Card. & Ther.) Grout, Moss Fl. N. Amer. 2: 134. 1935.

   Plants erect in small green to yellow green tufts, to 3 cm high. Leaves erect-spreading when moist but circinate-coiled and crispate when dry, narrowly lanceolate from an obovate base, to 4 mm long, about 5: 1. Median laminal cells isodiametric with rounded lumens, very thick walled with strong corner thickening, to 10 µm wide, with 1–3 papillae on both surfaces. Basal marginal cells to 12 µm wide, strongly differentiated up to distal portion of the obovate base, these cells rectangular, 3–5: 1, with straight lateral walls and with the transverse walls markedly thicker than those lateral walls. Basal juxtacostal cells linear, to 12 µm wide with lumen: wall ratio mostly less than 0.5: 1. Margins recurved at least at shoulders of the leaf, papillose-crenate distally but entire in basal 1/2. Costa ending within less than ten cells of apex. Costa cross-section about twice as broad as thick, about 3 cells thick with about 8 cells on abaxial perimeter, and with those abaxial cells markedly thicker-walled than the median or adaxial layers. Axillary hairs 4–6 cells long, nearly uniform in length across the leaf insertion, to 150 µm, with one basal brown cell and with the distal cells very thick walled (lumen: wall ratio 1–3: 1, not offset from leaf insertion. Rhizoids mostly near base of plant, smooth, thick-walled, red-brown, to 10 µm in diameter at base, repeatedly monopodially branched. Stem cross-section pentagonal, without a central strand, with somewhat pachydermous and pale inner corticals and with 1–2 layers of strongly pachydermous, red brown outer cortical cells.

   Autoicous with perigonia in leaf axils near the perichaetia. Perichaetia terminal with bracts somewhat smaller than vegetative leaves. Seta yellow to yellow brown, smooth, erect, to 8 mm long. Urn only gradually differentiated from the seta because of the long neck, to 2 mm long, 2–3: 1, yellow-brown and erect, strongly sulcate with eight ribs, only inconspicuously strangulate. Operculum short rostrate. Annulus poorly defined. Exothecial cells at capsule mouth similar in color to adjacent exothecial cells, to 18 µm broad, isodiametric with rounded lumens in up to 4 rows. Exothecial cells at middle of urn quadrate to rectangular, 1–2: 1, to 25 µm broad, with very thick lateral walls but thin transverse walls on ridges of capsule with lumen:wall ratio 0.25–1: 1, thinner-walled in valleys of the sulcate capsule. Stomata restricted to neck of capsule, cryptoporous, nearly obscured by subsidiary cells. Exostome teeth fused in pairs and appearing to be only 8 in number, hyaline to light brown, to 300 µm long, finely and densely fingerprint-stiate. Endostome segments 8, nearly as long as exostome, smooth to lightly papillose, arising from 2 irregular rows of cells. Calyptra cucullate-campanulate, rather densely clothed with rather thick and multiseriate, sparingly prorate hairs. Spores to 25 µm, rather coarsely papillose.

Vouchers: Del Norte Co.: French Hill Road about 2.5 miles above Highway 199, southwest of Gasquet, Six Rivers National Forest, Norris 85050 and Little Rattlesnake Mountain, Six Rivers National Forest, Wheeler 7390 (UC); Humboldt Co.: Blue Lake near Weitchpec, Norris 56340 and 2 miles south of the mouth of Mad River, Norris 7660; Trinity Co.: Highway 36 at Olsen Creek, Six Rivers National Forest, Norris 56631.

Illustration References: Ireland 1982; Smith 1978.

Elevation by latitude plot for Ulota obtusiuscula
   in California