木榄 mu lan

Rhizophora gymnorhiza Linnaeus, Sp. Pl. 1: 443. 1753; Bruguiera conjugata (Linnaeus) Merrill; R. conjugata Linnaeus.

Trees 6-20 m tall, d.b.h. 30-60 cm. Bark gray, deeply fissured. Stipules often reddish, ca. 4 cm, interpetiolar, caducous. Petiole 2-4.5 cm; leaf blade elliptic-oblong, 8-21 × 4-7(-9) cm, leathery, glabrous, base cuneate to rarely obtuse, apex acute. Pedicel 1-2.5 cm. Flowers in axils of upper leaves, solitary, red or pinkish red, ca. 3 cm. Calyx lobes 10-14, linear, 1.5-2 cm, glabrous. Petals 12-14, 1.3-1.5 cm, outer margin fringed with white silky hairs; sinus bristles 3 or 4 per petal, 2-3 mm, distinctly exceeding petals. Stamens twice as many as petals, 8-11 mm; filaments filiform; anthers linear to lanceolate, 4-5 mm. Disk cup-shaped. Ovary inferior, 3-loculed; style filiform, ca. 1.5 cm; stigma lobes 3 or 4. Fruit adnate to calyx tube, ca. 2.5 mm; persistent calyx on fruit or hypocotyls ribbed only apically. Seed 1, viviparous. Hypocotyl cigar-shaped, slightly angular, 15-25 × 1.5-2 cm. Fl. May-Jun. 2n = 26.

Mangrove forests; sea level. S Fujian, Guangdong, S Guangxi, Hainan, SW Taiwan (extinct) [Cambodia, India, Indonesia, Japan (Ryukyu Islands), Malaysia, Myanmar, Philippines, Sri Lanka, Thailand, Vietnam; E Africa, N Australia, Indian Ocean islands, Madagascar, New Guinea, Pacific islands].

Bruguiera gymnorhiza and Ceriops tagal were originally found among the mangroves of Gaoxiong (Kaohsiung) lagoon, Taiwan. Both species completely disappeared after 12 years (1956-1968) of expansion and second-stage construction of the harbor (1967-1977). The last gathering records indicate that in 1959 only 22 individuals of B. gymnorhiza and one individual of C. tagal remained in the lagoon (C. F. Hsieh, pers. comm.). According to C.-I Peng (pers. comm.), B. gymnorhiza disappeared from Taiwan in the 1960s.