Flora of North America species comparison

leaves triangular-lingulate to lingulate, 1.1–1.4 mm, apex broad-rounded to narrowly truncate, border very broad at base (more than 0.3 width);

hyaline cells efibrillose, rhombic, mostly 1-septate but can be non-septate.

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.

long and tapering, usually strongly 5-ranked.

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

ovate-lanceolate, 0.9–1.4 mm, concave, straight, apex involute;

hyaline cells on convex surface with very small ringed pores (less than 0.25 cell width) along commissures near apex, changing abruptly to large elliptical pores (0.4 cell width or more) basally, concave surface with large round pores in proximal margins and leaf base.

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.

17–26 µm, finely papillose on both surfaces;

proximal laesura less than 0.5 spore radius.

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

fascicles with 2 spreading and 1–2 pendent branches.

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

branch stems green, cortex enlarged with conspicuous retort cells.