Description from Flora of China
Shrubs to densely branched, small trees, maritime; all parts densely covered by grayish silky trichomes. Leaves opposite, sessile or subsessile. Flowers axillary, solitary or paired, 6-merous, actinomorphic, distylous. Floral tube turbinate, 12-ribbed; sepals short; epicalyx segments present, ca. 1/2 as long as or equaling sepals. Petals white or pale pink. Stamens 12, scarcely biseriate, inserted somewhat above base of floral tube, 6 exserted in short-styled flowers, all included in long-styled flowers. Ovary vestigially 3- or 4-locular, appearing 1-loculed with free, central placentation. Capsule dry, circumscissile, slightly exserted at maturity. Seeds irregularly obpyramidal, wingless.
Pemphis is now regarded as unispecific. See Graham et al., Koehneria, a new genus of Lythraceae from Madagascar (Ann. Missouri Bot. Gard. 73: 788-809. 1986).
One species: E Africa west across Indian Ocean to Marshall Islands in Pacific Ocean, north to China (Taiwan) and Japan (Ryukyu Islands).
(Authors: Qin Haining (覃海宁); Shirley Graham)