Sagittaria macrocarpa J. G. Smith, Rep. Mo. Bot
Gard. 6: 53. 1894.
Plants mostly emersed, 3-4 dm. tall ; leaves phyllodium-like, erect or nearly so, the blades rather imperfect, linear or linear-lanceolate, 5-7 cm. long, much shorter than the petioles ; scapes erect, overtopping the leaves ; whorls of the inflorescence 3-5, the lowest 2 whorls, or only the lowest, pistillate ; pedicels about as long as the internodes except those of the pistillate flowers, which are much shorter ; bracts ovate, about 3 mm. long, acute, united at the base; filaments dilated, pubescent; anthers about as long as the filaments; fruit-heads 10-12 mm. in diameter ; achenes obovate or oblong-obovate, 3 mm. long, winged, the beak ascending, rather stout;
Type locality : South Carolina.
Distribution : North Carolina and South Carolina.

Sagittaria macrocarpa, commonly called the large-fruited arrowhead, is an aquatic plant species known only from the US states of North Carolina and South Carolina.