Anoectangium Moss

This species is characterized by its ovate-lanceolate leaves, costa always ending below the leaf apex, and leaf margins crenulate at the base.

Plants of Anoectangium aestivum often exhibit a comal tuft, and have leaves with multifid or occasionally 2-fid papillae, these dense and obscuring the cell lumens. Specimens from Massachusetts identified as this species are Hymenostylium recurvirostrum. Sporophytes are rare in the flora area. Arizona specimens with blunt leaves have been named A. euchloron, representing a morphologically somewhat intergrading, wide-ranging tropical variant.

Plants slender, light green to yellowish green, (5–)10–20 mm high, in dense tufts or cushions. Stems erect, simple. Leaves densely arranged, 1.0–1.7 mm x 0.2–0.3 mm, appressed when dry, erect-spreading when moist, broadly lanceolate, keeled at the upper parts, gradually acuminate to acute at the apex; margins plane, entire or crenulate at shoulder portion of the leaf base; costa strong, ending below the apex, never excurrent; upper cells irregularly quadrate, 5–8 µm x 6–10 µm, with large, rounded, dense papillae; basal cells oblong-quadrate to linear-rectangular, hyaline, smooth, thick-walled, occasionally papillose, but always smooth near the costa. Setae 0.5–1.5 cm long, yellowish; capsules cylindrical or oblong-obovoid. Spores dull yellowish, smooth.

Leaves commonly distant and exposing the stem; short-lanceolate to ligulate, (0.4-)1-1.5(-1.8) mm; apex narrowly to broadly acute, apiculus short-triangular; margins 1-stratose; costa percurrent in distal leaves, ending in a clear, sharp cell. Specialized asexual reproduction absent. Sexual condition dioicous. Capsule 0.5-1 mm, exceeding the theca in length, ovoid, inclined.

Distribution: China, Japan, India, the Philippines, New Zealand, Europe, and North and South America.

Habitat: on rocks or rock crevices in alpine and subalpine regions.

Anoectangium compactum Schwaegr., Sp. Musc. Frond., Suppl. 1, 1: 36. 1811, nom. illeg. Anoectangium euchloron (Schwaegr.) Mitt., J. Linn. Soc., Bot. 12: 176. 1869. Gymnostomum euchloron Schwaegr., Sp. Musc. Frond., Suppl. 2, 2: 83. 1827.

Gymnostomum aestivum Hedwig, Sp. Musc. Frond., 32, plate 2, figs. 4-7. 1801; Anoectangium compactum Schwägrichen; A. euchloron (Schwägrichen) Mitten