Flora of North America species comparison

leaves quite variable in shape, elongate-lingulate to ovate, broadest above the middle, 1.9–2.5 mm, slightly concave, straight;

apex broad and toothed;

hyaline cells narrowly rhomboid, 0–1-septate, distal portion fibrillose, convex surface with membrane pleats, concave surface with 1(2–3) oblong membrane gaps.

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

rarely 5-ranked.

ovate, 1.6–2.2 mm, concave, straight;

apex stiffly involute and broadly truncate with up to 8 teeth, border denticulate due to cell wall resorption and projecting cell walls;

hyaline cells strongly bulging on convex surface and nearly plane on the concave surface, convex surface with narrowly elliptic pores along commissures grading from smaller pores near the apex to large rounded pores at base, concave surface with large round pores in proximal regions of leaf.

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.

monoicous.

monoicous.

with abundant pseudostomata.

27–33 µm, finely papillose on both surfaces with distinct bifurcated Y-mark sculpture on distal surface;

proximal laesura less than 0.5 spore radius.

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 with 2 spreading and 1–2 pendent branches.

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