Flora of North America species comparison

leaves 0.8–1.1 mm, triangular-lingulate to lingulate, concave, spreading, apex broadly obtuse, hyaline cells fibrillose in apical region.

leaves triangular-ovate, more than 1.2 mm, usually appressed;

apex acute to apiculate, hyaline cells rarely septate or porose, apical region often fibrillose.

slender and tapering, often 5-ranked and decurved, leaves somewhat elongated at distal end.

mostly unranked to weakly 5-ranked, often conspicuously falcate, leaves greatly elongated at distal end.

ovate-lanceolate, 1–1.7 mm, straight, slightly undulate and spreading;

margin entire, hyaline cells on convex surface with 1–5 pores in cell ends and free near apex, on concave surface with round wall thinnings in cell ends and angles; chlorophyllous cells triangular in transverse section and well-enclosed on concave surface.

ovate-lanceolate to lanceolate, 1.6–5 mm, falcate toward branch tips, when dry often undulate and recurved, rarely weakly serrulate along the margins in submerged forms, leaves from middle of spreading branches with length to width ratio less than or equal to 1:0.28;

hyaline cells length to width ratio in apical convex surface region 8:1 or more, convex surface with 0–1 small round pores at apex, concave surface with faint round wall thinnings in cell apices and angles; chlorophyllous cells triangular to trapezoidal in transverse section, broadly exposed on the convex surface and exposed slightly on the concave surface.

dioicous.

dioicous.

25–33 µm; smooth to finely papillose on both surfaces;

proximal laesura approximately 0.5 spore radius.

29–38 µm; covered with large papillae on both surfaces, appearing pusticulate;

proximal laesura less than 0.5 spore radius.

fascicles with 2 spreading and mostly 1 pendent branch.;

branch stem green, cortex enlarged with conspicuous retort cells.

fascicles with 2 spreading and 2–3 pendent branches.;

branch stems green, but often pinkish at the proximal ends, with cortex enlarged with conspicuous retort cells.