Coroll. Bry. Eur. 13. 1856. -- Bryum rufescens With., Syst. Arr. ed. 4, 3: 801. 1801.
Dicranella hutchinsonii Krajina, Bryologist 53: 153. 1950.
Plants to 8 mm high, scattered in open turfs, green to yellow-green mostly with reddish stems. Leaves spirally inserted without obvious ranking, to 2.5 mm long, 4–6: 1, lanceolate, gradually contracted to the blunt and channeled subula. Leaves erect and little distorted when dry, erect-spreading when moist. Lamina unistratose throughout, with all cells smooth. Cells of the leaf base in regular rows, to 12 µm broad, 4–8: 1, rectangular with very thin walls, without differentiated alar cells. Subula with lamina only 1–3 cells wide, with those cells rectangular to linear, to 10 µm broad, about 10: 1, arranged in regular rows, rather thick-walled with lumen: wall ratio 3–5: 1, with oblique end-walls. Margin minutely serrulate near base but nearly entire above. Abaxial cells of costa linear, to 8 µm wide, 6–10: 1; adaxial cells similar to adjacent laminal cells. Costa about 1/8 of leaf base but filling nearly all of subula, excurrent. Costa cross-section at mid-leaf round to hemispheric, nearly homogeneous. Margin plane below, somewhat erect above, serrulate above the middle. Rhizoids to 15 µm in diameter at insertion, red-brown, mostly on extreme base of plant. Axillary hairs to 75 µm long, 2–3 cells long, without basal brown cells and with all cells thin-walled and of uniform diameter throughout. Stem cross-section round to elliptical, with poorly defined central strand, very thin-walled inner cortical cells, and with one or two layers of thicker walled reddened cells in the outer cortex.
Dioicous with male and female plants similar. Perichaetial leaves larger and more sheathing than the vegetative leaves, with the basal 1/2 abruptly enlarged and sheathing. Seta to 10 mm, red to red-brown, straight, smooth. Capsule erect and symmetrical with the urn short cylindric, to 1.0 mm long, about 2: 1, neither sulcate and strangulate, not at all strumose. Annulus poorly defined. Operculum inclined, rostrate, 1/3 to 1/2 of urn length. Peristome reddish-brown, 180–250 µm long, densely lightly papillose, bifid to middle, strongly lamellate dorsally in proximal 1/2. Suboral exothecial cells transversely elongate, 2–3: 1, reddened, to 12 µm wide, thick-walled with lumen: wall ratio 2–3: 1. Exothecial cells rectangular with oblique end-walls and curved lateral walls, in regular rows, to 12 µm wide, 3–4: 1, thick-walled with lumen: wall ratio about 2: 1. Stomata mostly abortive, restricted to neck. Spores spherical, to 15 µm, finely papillose.
Dicranella rufescens may be identified in the field by its very small size along with the tendency to grow in very open turfs. It is usually fertile and is recognizable by the rather short capsules without any hint of sulcations.