Montana Field Guide

Plants: Pleurocarpous. Growing in open, interwoven mats (Lawton 1971), green, sometimes with added yellow tones, to brown (FNA 2014). Stems prostrate (Lawton 1971), erratically branched or pinnate; central strand thin; paraphyllia and hyalodermis not present; rhizoids or their initials arising from the stem or from the dorsal side of the costa at the leaf attachment, with few to many branches; axillary hairs with 1-4 transparent cells terminally (FNA 2014).

Leaves: Stem leaves lax to somewhat densely spaced, typically spreading to ca 90 degrees (Lawton 1971), sometimes nearly upright (FNA 2014), 0.7-1.5 mm in length, 0.2-0.5 mm in width (Lawton 1971), sometimes sickle-shaped, deltoid with soft corners to egg-shaped or widely so, cupped, not longitudinally folded, steadily tapering or abruptly narrowed to the apex, forming a long acumen (FNA 2014), the acumen usually either flat or involute (Lawton 1971), occasionally curved back and down, longitudinally grooved; base extending down the stem (FNA 2014); margins smooth, occasionally finely saw-toothed below (Lawton 1971), unbordered; costa typically single and mostly over half the leaf length (occasionally plants will have a few leaves with shorter double costae), without a dorsal spine (FNA 2014).

Leaf Cells: Alar cells numerous, somewhat small, the alar area ranging from square to deltoid (long crosswise), extending from the leaf edge to a little more or less than halfway to the costa attachment (occasionally to 80% of the distance), not clearly demarcated; margins 1 cell-layer thick; basal cells short, quadrangular to very thin; medial laminal cells quadrangular or very thin; upper cells smooth (FNA 2014).

Humus, tree bottoms and bare tree roots (Lawton 1971), soil and rock high in calcium or other minerals, the substrates wet or periodically wet; almost always below tree line (FNA 2016).

Dioicous. Interior perichaetial bracts longitudinally pleated (unlike the stem leaves). Seta to 35 mm tall (Lawton 1971), red. Capsule 2-3 mm in length (Crum & Anderson et al. 1981), bowed, level; exostome teeth with edges toothed or a little toothed above (FNA 2014), ochre; endostome segments without openings, the cilia grouped in 2’s or 3’s (Crum & Anderson et al. 1981), knobby or partly transversely ridged (FNA 2014).