Flora of North America species comparison

leaves equilateral to isosceles-triangular, small, less than 0.8 mm, mostly appressed to stem, apex acute to obtuse, hyaline cells efibrillose and nonseptate.

leaves long triangular-ovate, 1–2 mm; usually appressed;

apex acute to apiculate, hyaline cells only rarely septate or aporose but often fibrillose in apical region.

straight to slightly curved, usually 5-ranked;

leaves not much longer at distal end than proximal end.

unranked, straight to slightly curved, leaves somewhat elongated at distal end.

narrowly ovate-lanceolate, 0.8–1 mm, straight, moderately undulate and recurved in larger and/or wetter grown forms, not undulate and slightly recurved in compact forms from drier sites;

margins entire;

hyaline cells on convex surface with 1(2–3) pore per cell at apical end of cell, on concave surface with round wall thinnings in cell ends and angles; chlorophyllous cells triangular in transverse section and just enclosed on concave surface.

1.5–2.7 mm, ovate-lanceolate to lanceolate; straight to falcate toward branch tips; when dry often undulate and lightly recurved, margins entire to rarely weakly toothed along the margins in flaccid aquatic forms, hyaline cells on convex surface with 0–1 small round pores at apex, on 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 to broadly on the concave surface.

dioicous.

dioicous.

21–25 µm; coarsely papillose on proximal and distal surfaces;

proximal laesura more than 0.5 spore radius.

30–43 µm; the superficial surface coarsely papillose to papillose reticulate.

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

branch stems with cortex enlarged with conspicuous retort cells, often pinkish red at proximal end.

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

branch stems green, cortex enlarged with conspicuous retort cells.