Timmia Musc. Fr. Gen. 19. 3. 1822. -- Timmia austriaca Hedw. var. bavarica (Hessl.) Brid., Musc. Germ. 514. 1833.
Plants erect in olive-green to yellow brown tufts or cushions, to 2 cm high. Leaves ligulate-lanceolate with acute apices, to 6 mm long, 8–10: 1, erect spreading when moist but becoming canaliculate inrolled and somewhat hamate when dry. Median laminal cells of limb isodiametric to very short rectangular, 1–1.3: 1, with angular lumens, moderately thick walled without corner thickening, to 8 µm wide, high mammillose on adaxial surface, smooth on abaxial surface or with the basal juxtacostal cells of the limb sparingly low mammillose. Cells of leaf sheath hyaline, rectangular with straight lateral walls and with right angle transverse walls, to 10 µm wide, about 6–10: 1, smooth throughout. Margins plane throughout, dentate with multicellular teeth near apex but remotely serrulate throughout the remainder of the limb, not decurrent. Costa near base flattened and often somewhat inconspicuous, becoming stronger above, mostly 1.5–2: 1 at mid-limb, ending within about ten cells of apex. Costa cross-section with two strong stereid bands and a single layer of guide cells, usually with both epidermises well-demarcated. Axillary hairs numerous and persistent, more than 10 cells long, to 700 µm, without basal brown cells, not offset from leaf insertion. Rhizoids to 30 pm in diameter at insertion, closely low papillose, densely inserted at least near base of plant, red-brown, repeatedly branched, surrounding a macronematal area which is only 1.5–2 times as long as broad. Stem cross-section rounded-pentagonal, with a very strong central strand, leptodermous inner corticals and a single layer of somewhat thick-walled and mammillose outer cortical cells.
Dioicous with male plants somewhat smaller than females, bearing terminal perigonia. Perichaetia terminal with bracts gradually smaller than the vegetative leaves but not otherwise differentiated. Seta yellow to yellow brown, smooth, erect, to 15 mm long. Urn to 2 mm long, about 3: 1, inclined to almost erect, neither sulcate, nor strumose. Operculum dome-shaped or short apiculate. Annulus well-defined, revoluble. Suboral exothecial cells to 20 µm broad, elliptic and transversely elongate in 3–5 rows, with walls rather thick but without corner thickenings. Exothecial cells at middle of urn quadrate to short rectangular, 1–1.8: 1, to 40 µm broad, in regular vertical rows, rather thin-walled. Stomates phaneroporous, restricted to neck of capsule. Exostome inserted deeply below capsule mouth with teeth basally connate, pale yellow to yellow brown, to 400 µm long, undivided, striate below but distally finely papillose. Endostome including the high basal membrane, cross-striolate, about as long as exostome, without clear segments but instead with about 64 nodulose to appendiculate cilia. Calyptra cucullate, smooth. Spores to 12 µm, smooth or nearly so.