Sp. Musc. Frond., 176. 1801 ,
Plants (1–)2–9(–13) cm, in compact or loose tufts, brownish proximally, bright to yellowish green distally. Leaves crisped to imbricate (and occasionally inrolled) when dry, erect-patent to spreading when moist, (1.5–)2–8(–12) mm, 0.5–1.2 mm wide at mid-limb; cells of the sheath lamina longer and narrower near the margins, shorter and broader near the limb-sheath transition, smooth on the adaxial surface, smooth or with a series of linearly-arranged, large round papillae on the abaxial surface of the lumens. Sexual condition monoicous or dioicous; male gametophyte (in dioicous taxa) monopodial, with the stem continuing growth through terminal perigonia; paraphyses few, of 10–15(–40) cells, filiform, with fusiform tips; archegonia 1–6 per perichaetium, ca. 1–2 mm; antheridia 5–40 per perigonium, ca. 1–2 mm. Capsule ca. 2.5–3 × 1–1.5 mm; exothecial cells with smooth or sinuose walls; peristome diplolepideous; exostome teeth 0.5–1 mm, yellow in proximal half, pale or hyaline distally; endostome hyaline or yellowish, with a high basal membrane about half the height of the exostome, and 64 irregularly anastomosing, nodose cilia papillose externally and smooth or appendiculate on the interior surface. Spores round, finely papillose, pale yellow or brown, 13–22 µm.
North America, Eurasia, n Africa, Pacific Islands (Hawaii, New Zealand) in arctic, boreal, montane, and temperate areas.
Species 4 (4 in the flora).
|1||Cells at leaf insertion not hyaline and fragile, leaves not readily breaking away from stem||> 2|
|1||Cells at leaf insertion hyaline and fragile, leaves readily breaking away from stem [Sect. Norvegicae]||> 3|
|2||Leaf sheaths bright, clear orange (appearing red when still on the stem); cilia of endostome non-appendiculate; dioicous [Sect. Timmiaurea].||Timmia austriaca|
|2||Leaf sheaths pale, uncoloured or yellowish; cilia of endostome appendiculate; monoicous [Sect. Timmia]||Timmia megapolitana|
|3||Abaxial surface of mid-limb cells non-mamillose and non-papillose.||Timmia norvegica|
|3||Abaxial surface of mid-limb cells mamillose and pluripapillose (as seen in cross section).||Timmia sibirica|