Montana Field Guide

Plants: Pleurocarpous, typically growing in crowded tufts (Lawton 1971) or cushions (Crum and Anderson et al. 1981), green with brown tones to ochre (Lawton 1971) to somewhat red, glossy. Stems upwardly inclined to prostrate, typically sparsely and erratically branched, sometimes pinnate, 2-10 cm, russet to deep brown; branches 2-6 mm in length; hyalodermis lacking and central strand faint; pseudoparaphyllia broad and leafy (FNA 2014); cortical stem cells tiny and with thick walls (Lawton 1971).

Stem Leaves: Curved in sickle-like fashion to rolled nearly into a circle at the leaf apex and turned in one direction, 1.5-2 mm in length, to 0.6 mm in width (FNA 2014), cupped below (Lawton 1971), egg-shaped to lance-shaped, in either case with oblong tendencies (FNA 2014), slowly tapering to a long, thin, grooved acumen (Crum and Anderson et al. 1981), the base not extending down the stem; leaf edges flat, a little wavy or slightly and faintly saw-toothed; costa solitary or paired and the divisions differing in length; branch leaves akin to stem leaves (FNA 2014).

Leaf Cells: Laminal cells long and slender (Crum and Anderson et al. 1981), thick-walled (Lawton 1971), not papillose; medial laminal cells longer and the walls less porose than those of the basal cells; basal laminal cells colored yellow or somewhat ginger; alar cells deep brown, square to short and oblong (FNA 2014), or sometimes oddly shaped, the walls pitted (Lawton 1971), extending 6-7 cells up along the margin, distinct from adjacent cells (FNA 2014).

Fruit ripens in mid-summer (FNA 2014).

Porose laminal cells all over the leaf distinguish this from all other Hypnum species (FNA 2014).

Damp, calcareous soil or stone (Crum and Anderson et al. 1981), wet tundra in alpine areas (Elliott and Pipp 2016), usually in seepy places, dry tundra, open evergreen woods, typically living in calcareous habitats. Occurring from lowlands to about 8200 feet elevation (FNA 2014).

Dioicous, rarely producing sporophytes. Exterior perichaetial bracts bent back and downward; interior perichaetial bracts upright with a thin, smoothly-edged acumen, and margins fringed at the shoulders. Seta 13-20 mm tall, somewhat red, smooth. Capsule 1.3-1.5 mm in length, somewhat yellow, tilted to level (FNA 2014), bowed, shrunken below the opening when dry, the neck short (Crum and Anderson et al. 1981); operculum cone-shaped; exostome teeth 16, with a zigzag line on the outer face, fine lines or ridges below, and papillae above; endostome processes 16, similar in height as the teeth, keeled, cilia present. Calyptra hairless and draping hood-like (FNA 2014).