Flora of North America species comparison

leaves lingulate-spatulate, large, 1.3–1.6 mm; appressed to stem;

apex very broad and lacerate;

hyaline cells efibrillose and aporose, often septate.

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

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

strongly 5-ranked and straight.

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

ovate-lanceolate, 1.5–3 mm; straight to slightly subsecund; imbricate to somewhat reflexed and not undulate;

margins entire;

hyaline cells long and narrow, length to width ca. 10:1 on convex surface with 1 or more small pores in the cell ends and angles and often with numerous pseudopores along the margins, on concave surface with large round wall thinnings on the cell ends and angles; chlorophyllous cells triangular to trapezoidal in transverse section, apex often exposed 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.

monoicous or dioicous.

dioicous.

22–34 µm;

both surfaces smooth, apparent ridged border on proximal surface;

proximal laesura more 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 pendent branches, leaves not much elongated at distal end.;

branch stems green, with cortex enlarged with 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.