Flora of North America species comparison

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

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

leaves lingulate,small, equal to or less than 0.8 mm, appressed to stem;

apex with strong lacerate split in the middle;

hyaline cells efibrillose, aporose, and nonseptate.

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

strongly 5-ranked, short and blunt, not much elongated at distal end.

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.

ovate; usually less than 1.5 mm;

stiff and slightly reflexed, straight to slightly subsecund;

margins entire;

hyaline cells moderately long and narrow (6–8:1), convex surface with one small round pore per cell at apex and numerous pseudopores on the margin, concave surface with large round wall thinnings in the cell angles and ends; chlorophyllous cells triangular in transverse section, with apex reaching concave surface.

dioicous.

unknown.

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

proximal laesura less than 0.5 spore radius.

not seen.

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.

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

branch stems green, with cortex enlarged with retort cells.