Flora of North America species comparison

leaves equilateral to isosceles-triangular, small, less than 0.8 mm, mostly appressed to stem, apex acute to obtuse, hyaline cells efibrillose and nonseptate.

leaves lingulate to lingulate-triangular, 0.7–1.5 mm (to 3 mm in isophyllous forms), apex erose;

hyaline cells mostly 1–septate but in a few cells with 2–3 parallel septations, efibrillose to fibrillose throughout, pores present in hemiisophyllous and isophyllous forms.

straight to slightly curved, usually 5-ranked;

leaves not much longer at distal end than proximal end.

straight to somewhat curved, with spreading leaves.

narrowly ovate-lanceolate, 0.8–1 mm, straight, moderately undulate and recurved in larger and/or wetter grown forms, not undulate and slightly recurved in compact forms from drier sites;

margins entire;

hyaline cells on convex surface with 1(2–3) pore per cell at apical end of cell, on concave surface with round wall thinnings in cell ends and angles; chlorophyllous cells triangular in transverse section and just enclosed on concave surface.

variable, broadly ovate to ovate-lanceolate, 1.3–5 mm; straight, hyaline cells on the convex surface with 4–8 µm round to elliptic pores in nearly continuous rows along the commissures, the concave surface aporose or with some porosity as on the convex surface.

dioicous.

unknown.

not seen.

21–25 µm; coarsely papillose on proximal and distal surfaces;

proximal laesura more than 0.5 spore radius.

not seen.

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

branch stems with cortex enlarged with conspicuous retort cells, often pinkish red at proximal end.

fascicles with 2 spreading and 2 pendent in emergent forms, these reduced in aquatic forms to 2 per fascicle.