Flora of North America species comparison

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.

leaves lingulate to triangular-lingulate, 0.9–1.2 mm, apex rounded, usually 1/3–1/2 of leaf fibrillose;

hyaline cells usually fibrillose in distal 1/3–1/2 of leaf, on convex surface near apex with 1–3 pores per cell, on concave surface near apex 1–4 pores per cell.

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

arched but rarely curved and contorted.

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.

ovate, 1–1.5 mm, straight to slightly subsecund;

hyaline cells of convex surface with numerous ringed pores along the commissures (12–22 per cell), 0–3 pores per cell on the concave surface.

dioicous.

with few pseudostomata.

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

30–37 µm; finely papillose on both surfaces, indistinct raised Y-shaped sculpture on distal surface;

proximal laesura 0.5 spore radius or less.

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

branch stems green, cortex enlarged with conspicuous retort cells.

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