Montana Field Guide

Plants: Growing in open, upright clumps or turfs, olivaceous above, brown below. Stems upright, spreading to ca 45 degrees, or creeping, 2-4 cm, sometimes reaching 8 cm, few-branched; central strand not present (FNA 2007).

Leaves: Upright and flat against the stem when dry, spreading to ca 45 degrees when wet, 2.2-3.8 mm in length, 0.5-0.8 mm in width, a little bowed to straight; margins undulate, curved back and downward up to 3/4 the leaf length on both sides; costa reaching the apex, the dorsal surface strongly rounded and with a dorsal, slightly off-center, longitudinal channel interrupting the convexity; hair-pointed, the awns 0.3-0.8 mm in length, finely and sharply toothed, not decurrent, round in X-section (FNA 2007).

Leaf Cells: Costa in X-section with the boundary outline noticeably asymmetric, from 3-5 cell-layers thick proximally, transitioning to 2-3 layers above, with 2-5 dorsal cells proximally, transitioning to 2-3 above; margins of 2 cell layers above in 1 or 2 (occasionally more) rows, sometimes with patches having 3-4 cell layers; laminal cells 1-layered with lengths of 2-layers here and there, smooth; middle and upper cells square to oblong, frequently becoming wider than long at the leaf edges; basal laminal cells long and narrow, wavy, minutely knobbed, and with spiraled thickenings near the attachment; alar cells only a little modified (FNA 2007).

The asymmetric costa with its winged appearance in X-section is unique in the genus (FNA 2007).

Dry to somewhat wet stones and bluffs; acidophile. Elevation: 0-5250 feet (FNA 2007).

Seta 1-3 in a perichaetium, twisted clockwise above, 4-7 mm in length, somewhat ochre. Capsule 1-3 mm in length, a little creased when dry, shiny to dull brown; beak of operculum sometimes tilted; peristome dentitions papillose, lance-shaped, perforated or occasionally ruptured above into 2 lobes, brown (FNA 2007).