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 1.1 × 1 mm; rarely hemiisophyllous;

hyaline cells non-ornamented, frequently septate.

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

clavate and rounded 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.

broadly ovate, 2.4 × 1.7 mm;

hyaline cells on convex surface with numerous round pores along the commissures, comb-lamellae on hyaline cell walls where overlying chlorophyllous cells; chlorophyllous cells broadly triangular in transverse section and well-enclosed on the convex surface.

dioicous.

dioicous.

with pseudostomata.

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

proximal laesura less than 0.5 spore radius.

22–29 µm; finely papillose on both surfaces;

indistinct triradiate ridge on distal surface;

proximal laesura 0.5–0.6 spore radius.

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 pendent branches.;

branch stems with hyaline cell comb-lamellae visible on interior cortex wall, cortical cell end walls with conspicuous funnel projections more than 1/2 length of cell, superficial cortical wall aporose.