22. Tortula laureri (Schultz) Lindberg, Öfvers. Kongl. Vetensk.-Akad. Förh. 21: 243. 1864.
Trichostomum laureri Schultz, Flora 10: 163. 1827; Desmatodon laureri (Schultz) Bruch & Schimper
Leaves elliptic, apex broadly acute to rounded-acute, mucronate or apiculate, occasionally obtuse, margins recurved at mid leaf, 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. Capsule 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; high elevations (2800-3800 m); Greenland; Alta., B.C., Nfld. and Labr. (Nfld.), N.W.T., Nunavut; Alaska, Colo., Mont., Utah; Europe; Asia; s Africa.