Authors: Dr. Guy R. Brassard

Plants robust. Leaves 3--8(--12) mm, 0.8--1.1 mm wide at mid-limb; cells of mid-limb lamina (8--)9--16(--18) X (8--)9--14 µm; costa ending below apex, papillose on abaxial surface of sheath and limb; base of costa dark and swollen, more strongly attached to stem than is the lamina; with distal leaves often larger and deciduous, but never with loose clusters of linear leaves at stem tips.

Sporophytes extremely rare; only three sporulating specimens are known (1 from Alaska); the deciduous leaves undoubtedly act as vegetative propagules. In wet calcareous sites such as seepage slopes, moist crevices or cliff ledges, snowpatches, and edges of small creeks and ponds in arctic-montane areas; often intermixed with other mosses, including T. sibirica, T. norvegica var. excurrens, and T. austriaca; 0--3600 m; Greenland; Alta., B.C., Man., Nfld., N.W.T., Que., Yukon; Alaska, Colo., Mont.; Eurasia (Iceland, U.K., Scandinavia, Alps, Russia); disjunct to Southern Hemisphere (New Zealand).