Compilation
Marsilea macrocarpa

Loosely caespitose plant; rhizome slender to stout, 0.1–1.75 mm thick, pilose or glabrous, often villous or tomentose at the nodes. Stipes variable, slender or rarely stout, (5–)10–25 (in some aquatic forms –40) cm long, usually glabrous, somewhat striate. Leaflets greyish-green to dark green, sometimes glossy on the upper surface, broadly obtriangular, more rarely narrowly obtriangular-cuneate, often broader than long, (4–)7–25(–35) mm long, (3–)5–28(–40) mm wide, sides usually concave, sometimes straight, very rarely slightly convex; outer margin round, entire or sinuate, sometimes crenulate, or crenate-dentate, rarely lobed, with long brown suberose interstitial streaks on the lower surface of floating fronds, glabrous (in aquatic forms) or pilose at first and becoming glabrous (in terrestrial forms), rarely remaining pilose. Pedicels erect or ascending, rarely growing horizontally, slender or rarely somewhat stout, free from each other, inserted at the very base of the stipe, (3.5–)7–12(–14) mm long, usually pilose, rarely glabrous; the angle between the longitudinal axis of the sporocarp and the pedicel varying from 90–180°. Sporocarps usually several, rarely solitary, brown, usually broadly elliptic or broadly elliptic-oblong, but also obtusely rectangular to subcircular in lateral view, narrowly rectangular to slightly biscoctiform in dorso-ventral cross-section, very variable in size, (3.2–)4.2–6(–7) mm long, 3–4.5(–5.5) mm high, 1.5–2 mm thick, not bordered, usually with a shallow furrow along the dorsal and frontal side, which sometimes extends down to the base of the ventral side, densely appressed pilose at first, sometime villous or rarely tomentose, later becoming more sparsely pilose, rarely entirely glabrous at maturity; lateral ribs more or less distinct, often disappearing in fully mature sporocarps; lateral veins (as seen on the interior surface) not anastomosing; raphe always distinct, covering 1/3–1/2 (rarely 2/3) the length of the sporocarp base; inferior tooth absent or only a very shallow hump; superior tooth present, rather short, conical, obtuse or very rarely subacute to acute. Sori 8–12(–14). Fig. 1.10 (page 4).