Flora of North America species comparison

leaves to 1.7 × 1 mm, occasionally longer; rarely hemiisophyllous;

hyaline cells non-ornamented, nonseptate.

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.

long and tapering, leaves ± imbricate to spreading in shade forms.

rarely 5-ranked.

broadly ovate, 2.2 × 1.3 mm, hyaline cells non-ornamented, convex surface with elliptic pores along the commissures, chlorophyllous cells isosceles-triangular to ovate-triangular in transverse section and just enclosed to just exposed on the convex surface;

end wall not thickened.

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.

dioicous.

monoicous.

with numerous pseudostomata.

24–33 µm, surface finely papillose to smooth, distal surface with distinct bifurcated Y-mark sculpture;

proximal laesura more than 0.6 spore radius.

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.

fascicles with 2 spreading and 2 pendent branches.;

branch stems with hyaline cells non-ornamented;

no or weak funnel-like projections on the interior end walls, often with 1 large pore per cell on superficial cell walls.

fascicles with 2 spreading and 1–2 pendent branches.