Obovate Andreaea Moss

Like Andreaea alpina, A. obovata has spores in two size classes, the smaller apparently abortive. It is very rare in the flora area and can be distinguished from A. rupestris by the panduriform leaves.

Plants red-brown to purple-black. Leaves straight to secund, panduriform, widest in distal half, apex usually symmetric; costa absent; leaf margins entire; basal laminal cells rectangular to long-rectangular, marginal cells rectangular, walls thick, pitted-nodose; medial laminal cells quadrate, 1-stratose, lumens irregularly stellate to rhombic; laminal papillae low or absent. Sexual condition autoicous; perichaetial leaves differentiated, convolute-sheathing. Spores 20-35 µm.

Andreaea obovata Thed. Bot. Notiser 1849: 78. 1849 Plants densely pulvinate, the tufts brown or almost black; stems 2-4 cm. high, slender, often naked at the base ; branches fastigiatc and numerous : leaves imbricate, erect-appressed when dry, the upper half spreading or incurved when moist, from an erect, clasping base; symmetric, oblong-ovate or panduriform; upper half broadly acuminate, 0.9-1.25 mm. long, ecostate and nearly smooth, mamillose, or with brown, not hyaline papillae on the back; margins incurved, entire or slightly crenulatc above; apex blunt; basal cells linear, sinuous and porose, the upper cells shorter, with very thick walls and irregularly angled, rhombic or rounded lumen; leaf-section showing a single layer of brown-walled cells, flat on the inner surface, mamillose on the outer; perichaetial leaves erect, convolute, 2-3 mm. long, broader above the middle, often hyaline or erose at the apex; cells linear, sinuous, porose. Autoicous: antheridia often on separate, slender branches: pseudopodium often slightly exserted or immersed: calyptra hyaline, lobed: capsule about 1 mm. long, split three-fourths of the way to the base, with a short, pale neck: spores smooth, green or brown, globose or ovoid, 21-27 ^ in diameter, maturing in summer.
TvpR IX5CALITV: Sneehatten, Dovrefjeld, Norway. Distribution: Greenland; also in Scandinavia and Spitzbergen.