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 triangular to lingulate-triangular, equal to or more than 0.8 mm, spreading to appressed;

apex acute to apiculate, hyaline cells mostly efibrillose and nonseptate.

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

± straight and somewhat tapered, usually 5-ranked, leaves not greatly elongated at branch 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.

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

hyaline cells on convex surface with 1 pore per cell in apical end, on concave surface with round wall thinnings in the cell ends and angles; chlorophyllous cells in transverse section triangular to ovate-triangular and well-enclosed on the concave surface.

dioicous.

dioicous.

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

proximal laesura less than 0.5 spore radius.

24–33 µm; finely papillose on the superficial surface.

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 and often reddish at proximal end, with cortex enlarged with conspicuous retort cells.