Flora of North America species comparison

leaves triangular to triangular-lingulate, 1–1.3 mm, apex acute to slightly obtuse, border broad at base (more than 0.25 width);

hyaline cells narrowly rhomboid, mostly 0–1-septate and mostly efibrillose.

leaves triangular, large, less than 1.7 mm, mostly appressed to stem, apex weakly apiculate to narrowly obtuse;

hyaline cells efibrillose and seldom to often septate at base and sides.

usually strongly 5-ranked.

unranked, long and tapering, leaves greatly elongate at distal end.

ovate to ovate-lanceolate, 1.1–1.5 mm, concave, straight, apex slightly involute;

hyaline cells on convex surface with numerous oval to elliptic pores along commissures grading from small pores near apex to large round pores at base, concave surface with large round pores in proximal portions of leaf.

ovate-lanceolate to lanceolate in aquatic forms, ovate to ovate-lanceolate in emergent forms, greater than 2.5 mm, often falcate-secund, especially in submerged forms, weakly undulate and recurved when dry;

margin entire, hyaline cells on convex surface with 0–1 pores per cell, concave surface with round wall thinnings in the cell apices and angles; chlorophyllous cells narrowly triangular in transverse section and well-enclosed on the concave surface.

monoicous or dioicous.

dioicous.

19–27 µm, finely papillose on proximal surface, pusticulate on distal surface;

proximal laesura less than 0.4 spore radius.

fascicles with mostly 3 spreading and 1–2 pendent branches.

fascicles with 2 spreading and 2 pendent branches.;

branch stem green, cortex enlarged with conspicuous retort cells.

not seen.