Flora of North America species comparison

leaves small, 0.3–0.7 mm, triangular-lingulate with broad rounded apex, Branches short, crowded, and unranked.

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.

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

large, 1.4–3 mm, semi-squarrose to squarrose, ovate and abruptly involute in distal portion, appearing cucullate with toothed apex, usually no more than 6 teeth;

hyaline cells with 5 or more ringed, round to elliptical pores on convex surface, numerous pseudopores on concave surface with 3-ringed corner pores occurring in 3s at adjacent cell angles; chlorophyllous cells elliptic in transverse section, entirely included by hyaline cells, slightly nearer to convex surface.

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.

dioicous.

with abundant pseudostomata.

25–35 µm; finely papillose on proximal surface, coarsely papillose on distal surface with raised Y-mark sculpture;

proximal laesura short, 0.3–0.5 spore radius.

fascicles 4–6 branches per fascicle, 2–3 spreading and 2–3 pendent, but plants frequently unbranched in young clones.

fascicles with 2 spreading and 2 pendent branches.;

branch stem green, cortex enlarged with conspicuous retort cells.

not seen.