Montana Field Guide

Plant: Acrocarpous (Vitt 1988). Loose or dense tufts. Green to yellow-green, sometimes glaucous. Stems 1-10 cm tall, sometimes branched, and often with clusters of brown rhizoids.

Leaf: Imbricate to erect-spreading, straight or sometimes a little secund, ovate to ovate-lanceolate, 1.5-2.0 mm long, and at least the base is plicate. Margins revolute (sometimes only at base), serrate (often with double teeth). Costa percurrent to excurrent.

Leaf Cells: Upper leaf cells usually linear to oblong (sometimes short), walls thickened, and with a single papilla at one end of each cell or sometimes at both ends. Basal leaf cells usually smooth, broader, and cell walls thinner.

Philonotis fontana var. caespitosa: Present in Montana (Elliott & Pipp, 2016). Stems short to tall, sometimes reaching 20 cm in height. Leaves upright and overlapping to spreading, lance-shaped with ovate tendencies, flat or with 2 longitudinal pleats below (FNA 2014); costa extending to or slightly beyond the leaf tip (Lawton 1971).

Philonotis fontana var. americana: Present in Montana (Elliott & Pipp, 2016). Stems somewhat short to tall, occasionally reaching 16 cm in height. Leaves laxly spaced, spreading, chain-like, widely lance-shaped with ovate tendencies, occasionally curved like a sickle, with several longitudinal pleats, the uppermost leaves going around the stem in spiral-fashion (FNA 2014); costa extending beyond the leaf tip (Lawton 1971).

Philonotis fontana var. pumila: Present in Montana (Elliott & Pipp, 2016). Stems short, occasionally reaching 6 cm in height. Leaves densely spaced to lax, somewhat rigidly upright, sometimes strongly pointing to one side of the stem, lance-shaped, lacking pleats (FNA 2014); margins typically revolute their entire length (Crum & Anderson et al., 1981); costa extending well beyond the leaf tip (Lawton 1971).

Variety caespitosa: Fruit ripens throughout the year.

Variety americana: Fruit ripens early through late summer.

Variety pumila: Fruit ripens early summer through mid-summer.

Reference: FNA 2014 (28:111-112).

When submerged for extended periods, plants may exhibit atypical characteristics (FNA 2014).

Leaves of P. fontana, when living, may appear waxy and bluish (Crum & Anderson et al., 1981).

Distinguishing characteristics of variety americana include the chain-like leaf arrangement and uppermost leaves attached around the stem in spiral fashion (FNA 2014).

The stems of variety pumila, which forms mats, are very crowded, their rhizoids enmeshed into tomentum (FNA 2014).

Variety caespitosa: Wet soil and rocks in open places along streams and seeps. From lowlands to ca 11,480 feet.

Variety americana: Wet soil in open places along streams and seeps, inclines, montane grasslands. From lowlands to ca 9840 feet.

Variety pumila: Wet soil along streams, seeps, and wet inclines. From lowlands to ca 10,830 feet.

Reference: FNA 2014 (28:111-112).

Dioicous. Perigonia plate-like. Seta 2-7 cm tall. Capsules 1-3.5 mm in length, ribbed when dry; operculum mammillate; exostome divisions russet, lance-shaped, heavily papillose; exostome segments ochre to yellow, strongly folded longitudinally.

Variety caespitosa: Capsule sometimes reaching 3 mm in length.

Variety americana: Capsule sometimes reaching 3.5 mm.

Variety pumila: Capsule sometimes reaching 2 mm.

Reference: FNA 2014 (28:106, 111-112).