Trichostomum laureri Schultz
Leaves elliptic, apex broadly acute to rounded-acute, mucronate or apiculate, occasionally obtuse, margins recurved at midleaf, bordered throughout or in lower 2/3 with 2(--3) rows of narrower, short- to long-rectangular, thicker-walled, somewhat less papillose cells that are 1--2-stratose; costa percurrent or short-excurrent, lacking an adaxial pad of cells, distally narrow, 3--4 cells across the convex adaxial surface; distal laminal cells hexagonal to rectangular, 16--21 µm wide, 1--2:1, strongly 2-fid papillose. Sexual condition autoicous. Sporophytes exerted. Seta 0.9--1.5 cm. Capsules stegocarpic, not systylius, cylindric, horizontal or pendent, nearly straight, urn 1.8--2.5 mm; peristome 300--500 µm, teeth 16, weakly twisted to twisted 1 turn, divided nearly to the base into 2--3 branches and variously perforate, basal membrane low, ca. 50 µm; operculum 0.5--1.2 mm. Spores 18--23(--35) µm, spheric, densely papillose.
Capsules mature summer. Soil, rock crevices, especially calcareous substrates, tundra, essentially subalpine; 2800--3800 m; Greenland; Alta., B.C., Nfld., N.W.T., Nunavut; Alaska, Colo., Mont., Utah.; Europe; Asia; s Africa.