Montana Field Guide

Pleurocarpous (Vitt 1988), growing in open mats or sometimes in clumps with somewhat upright branches (Lawton 1971), pale green as juveniles, eventually turning somewhat yellowish to ochre. Stems prostrate, sometimes reaching 10 cm in length, crowded with pinnate branching, possessing a central strand; branches 5-7 mm in length, rounded to wound nearly into a circle at the apex (FNA 2014) or sometimes straight (Lawton 1971).

Stem Leaves: Overlapping, upright and next to the stem, 0.7-2.8 mm in length, to 0.8 mm in width, strongly pleated, lance-shaped and somewhat deltoid with the apex narrowing slowly or forming an acumen, and the base slenderly extending down the stem; leaf edges finely saw-toothed to nearly smooth, flat or curved back and downward here and there; costa extending over 2/3 of the leaf length to approaching the leaf tip, stout throughout, ending with a spine (FNA 2014) or occasionally not spined (Lawton 1971).

Branch Leaves: Flat against the stem when dry, spreading to over 45 degrees when wet, 0.5-1.8 mm in length, to 0.4 mm in width, slender and lance-shaped, ending in an acumen; leaf edges saw-toothed below, sometimes finely so, flat or curved back and downward here and there; costa length as in stem leaves, varying in length on the same shoot, with a spine at the end (FNA 2014).

Cells of the Stem Leaves: Laminal cells very slender and bent or curved; basal cells somewhat egg-shaped and long, the region arranged into 1-3 series of cells and that is obscurely different from the cell area above (FNA 2014); medial cells 10 times or more longer than wide, slightly longer than the basal cells, thick-walled (Lawton 1971); alar cells egg-shaped and thick-walled, somewhat distinct from adjacent cells (FNA 2014).

Cells of the Branch Leaves: Laminal cells very slender and bent or curved; basal cell region arranged into 1 or 2 series of cells; upper cells smooth; alar region of nearly square to somewhat egg-shaped cells and well-defined (FNA 2014).

Homalothecium fulgescens, which also sometimes has irregularly pinnate branching, has alar cells that are somewhat irregularly shaped rather than evenly square-shaped, and its capsules are less strongly bowed (FNA 2014).

Stone and soil (FNA 2014), frequently calcareous, seldom on tree trunks and decaying wood (Lawton 1971), amongst trees and in exposed habitats. Occurring from lowlands to 7550 feet (FNA 2014).

Phyllodioicous or dioicous, the stems and rhizoids of large female plants supporting epiphytic dwarf males, or male plants similar to the females and growing intermixed in the same clumps or in separate clumps (FNA 2014). Perigonial leaves abundant, cupped, without a costa. Interior perichaetial leaves to 5 mm or more in length, the costa absent or faint (Lawton 1971). Seta russet, 7-15 mm tall, coarse nearly throughout, or sometimes smooth near the apex. Capsule russet, 1.8-2.5 mm in length, tilted to level, sometimes almost upright, bowed; operculum shaped like a tall cone; peristome allowing capsule mouth to open in conditions of high humidity (FNA 2014); exostome teeth 16 with delicate horizontal lines or ridges (Lawton 1971); endostome processes not shorter than exostome teeth (FNA 2014), perforate on the keel (Lawton 1971); cilia similar in height as the processes. Calyptra without hairs (FNA 2014), and draping like a cowl (Lawton 1971).