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, 1–1.2 mm, apex entire to somewhat erose;

hyaline cells non-septate;

fibrillose and porose in apical region.

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

slender with small spreading leaves.

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-lanceolate, 1.4–1.6 mm, straight to slightly subsecund, weakly undulate, often recurved in capitulum branches;

hyaline cells on convex surface with up to 5 small round faint pores per cell in the basal portion of the cell and free from the cell margins, concave surface aporose.

dioicous.

unknown.

not seen.

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 pendent branches.