Flora of North America species comparison

to 20 per plant, blackish, usually extremely narrow, often almost hairlike, less than 0.1 mm diam., proliferations not reported.

yellowish to pale brown, to 15 per plant, 0.2-0.8mm diam., proliferous at wide intervals.

spheric, 3-12 mm diam., succulent, cormlike with perforation at apex, apical meristem located at bottom of cavity through which leaves emerge at top, leaves 2 per stem.

upright, 0.2-1.2 cm, 1-5 mm diam., commonly 2-3 leaves per stem.

stalk to 0.6cm, 0.1-0.2 times as long as trophophore blade.;

trophophore blade lying nearly flat on ground, not folded longitudinally, pale green throughout, deltate to cordate, to 3 × 2 cm, contracted abruptly at truncate to cordate base, apex with apiculum.

stalk to 0.8 cm, 0.1-0.2 times length of trophophore blade.;

trophophore blade spreading, usually plane when alive, green, dull, largest leaves drying with pale central band, ovate to lanceolate, thin, blades less than 0.4 × 0.3 cm in many colonies but blades large, to 4.5 × 1.7 cm in other colonies, herbaceous, base gradually tapered, apex with short apiculum;

venation finely complex-reticulate, areoles with only included veinlets in smaller blades but with numerous secondary areoles in largest blades.

coarsely reticulate with included veinlets.

arising at ground level, 1-5 times as long as trophophore;

sporangial clusters usually short, less than 1 cm, 2-3 mm wide, with 3-8 pairs of sporangia, apiculum to 1.5 mm.

arising at or near ground level, 2-6 times as long as trophophore;

sporangial clusters 0.5-1.5cm, 1.5 mm or less wide, mostly with 5-12 pairs of sporangia, apiculum 0.5-1 mm.