Japan Flora: Perennial herb; stems creeping, sparingly branched, rooted at the nodes; leaves petiolate, narrowly oblong to elliptic-ovate, 15-25 mm. long, 6-15 mm. wide, entire, rounded at apex, smooth, with 3 principal veins and 10-20 pairs of connecting veinlets, the petioles purplish, with a hyaline membranous scale at base; pistillate flowers axillary, sessile, 2-bracteate. On sandy sea bottoms.
Honshu (Sagami, Noto and westw.), Shikoku, Kyushu. India, Malaysia, and Australia.