1. Pemphis acidula J. R. Forster & G. Forster, Char. Gen. Pl. 34. 1775.
水芫花 shui yuan hua
Shrubs to densely branched, spreading trees, maritime, small, to 11 m tall, but often ca. 1 m. Stems and branchlets ascending; branchlets, young leaves, and inflorescences densely silky grayish white strigose. Leaves opposite, sessile or subsessile; petiole to 2 mm; leaf blade narrowly elliptic to lanceolate, 1-3 cm × 5-15 mm, thick, succulent, base attenuate, apex often terminating in a minute circular hydathode. Flowers solitary or paired, axillary, 6-merous, actinomorphic, heteromorphic, distylous; pedicel 5-13 m. Floral tube 4-5 mm, turbinate, 12-ribbed, thick walled, densely grayish white strigose; sepals short, ca. 1/4 as long as floral tube; epicalyx segments equaling sepals or ca. 1/2 as long. Petals 6, white or pale pink, obovate to suborbicular, 3-5 mm. Stamens 12, scarcely biseriate, 6 exserted in short-styled thrum flowers, all included in long-styled pin flowers. Ovary vestigially 3- or 4-loculed, appearing 1-loculed with free central placentation at maturity; ovules ascending on short placenta; style long-exserted in pin flowers, included in thrum flowers; stigma capitate. Capsules dry, circumscissile, obovoid, ca. 6 mm, slightly exserted at maturity. Seeds ca. 20, irregularly obpyramidal, not winged, 2-3 mm. 2n = 32.
Tropical sandy shores, inlets in mangrove forests. S Taiwan [E Africa west across Indian Ocean to Marshall Islands in Pacific Ocean, north to Japan (Ryukyu Islands)].