Flora of North America species comparison

radially symmetric, underground (rhizomatous) and aerial, not readily fragmenting, irregularly forked;

both rhizomatous and aerial stems often with 1 branch arrested, budlike, tips straight; rhizomatous stems hard to distinguish on wholly creeping plants;

aerial stems erect or ascending, sometimes decumbent to slightly creeping, budlike arrested branches restricted mostly near stem base.

radially symmetric, creeping or decumbent, not readily fragmenting, irregularly forked, without budlike arrested branches, tips straight;

main stem indeterminate, lateral branches conspicuously or inconspicuously determinate, often strongly ascending, 1–3-forked.

dimorphic, not clearly ranked.

monomorphic, in alternate pseudowhorls of 5, tightly appressed, ascending, green, linear-lanceolate to narrowly lanceolate, 2–3.5 × 0.35–0.5 mm (smaller on lateral branches);

abaxial ridges prominent;

base cuneate and decurrent to rounded and adnate on young lateral branches or buds, glabrous or sometimes pubescent;

margins long-ciliate, cilia transparent, spreading to ascending, 0.07–0.17 mm;

apex keeled, truncate in profile, obtuse to attenuate;

bristle white to whitish or transparent, puberulent, 0.45–0.8 mm.

solitary, 0.5–2.5(–3.5) cm;

sporophylls lanceolate, strongly tapering toward tip, abaxial ridges prominent, base glabrous, margins short-ciliate, apex long-bristled.

solitary, 0.5–2.5 cm;

sporophylls deltate-ovate to ovate-lanceolate, abaxial ridges well defined, base glabrous, margins ciliate, apex truncate in profile, bristled.

borne on upperside of stems, restricted to lower stems or throughout stem length, 0.3–0.5 mm diam.

borne on upperside of stems, throughout stem length, 0.2–0.37 mm diam.

stem leaves persistent or deciduous, tightly appressed, scalelike.

stem leaves appressed, ascending, green, linear-lanceolate, 3–4.7 × 0.45–0.65 mm;

abaxial ridges present;

base abruptly adnate, rounded, pubescent;

margins long-ciliate, cilia white to whitish, spreading, 0.1–0.2 mm;

apex not keeled to slightly keeled;

bristle white to whitish or yellowish to greenish near base, puberulent, 0.65–1.85 mm (1/3–1/2 length of leaves).

= 18.