Flora of North America species comparison

leaves triangular to lingulate-triangular, 0.8–1.2 mm, mostly appressed to the stem, apex acute to apiculate, hyaline cells mostly efibrillose and nonseptate.

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

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

straight, mostly unranked, but can be 5-ranked in wet-growing forms, leaves little elongated at distal branch ends.

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

ovate-lanceolate, greater than 1.2 mm, straight, undulate and sharply recurved when dry, margins entire;

hyaline cells on convex surface with usually 1 round pore per cell at apical end, on concave side with round wall thinnings in the cell ends and angles; chlorophyllous cells triangular and just reaching or slightly enclosed within the 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.

25–31 µm;

proximal surface finely papillose, distal surface pusticulate with bifurcated Y-mark sculpture;

proximal laesura less than 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 2–3 pendent branches.;

branch stems green but proximal end sometimes red, with 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.