Rhizophora mucronata Lam.
Eng.: Loop-root mangrove, red mangrove, Asiatic mangrove. Spa.: Mangle. Fre.: Mangrove.
Tree or shrub, evergreen, up to 8(10) m in height (some specimens cited as 18 m), typically without a well defined main trunk from the ground. The “base” of the trunk is elevated on a set of aerial roots forming a type of dome of 1 or more m in height; on the top of this dome the roots progressively converge shaping a single trunk that soon branches. Bark greyish or orange-grey, smooth, on branches with elliptical scars left by the base of the petioles of fallen leaves. Leaves opposite (6-15 × 4-9 cm) coriaceous, glabrous, elliptical to obovate-elliptical, entire, with acute or obtuse apex but always mucronate, rounded or cuneate base; green yellowish when young, turning dark green above as they mature, and slightly lighter beneath. Midrib very prominent, secondary veins hardly visible. Petiole 2-4 cm. Stipules 6-8 × 1.5-2 cm, acute. Inflorescence in axillary pendulous cymes, with 6-12 pentamerous flowers, with main peduncle 2-4 cm and pedicels about 5 mm. Bracts 1.5-2 mm, coriaceous, persistent. Calyx campanulate, thick, white-greenish, with tube of about 4 mm and lips about 12 mm, ovate, with an acute apex. Petals 8-10 mm long, narrowly ovate to oblong-lanceolate, acute, with long whitish hairs and lanate margins, fleshy, whitish-yellow, that extend between the sepals not over them. Ovary about 4 mm, ovoid-conical. Stamens 8. Fruit an ovoid brown berry, hard, with 1-2 seeds developing inside (viviparity) resulting in an elongated propagule or hypocotyl (up to 40 × 1.2 cm) circular in cross section, thinly narrowing at the ends, first green, turning dark grey-brown, with lenticels. This propagule is formed on the tree and when it falls it can root directly on the ground or, as it can float in water, it can be carried by ocean currents hundreds of km and root in any tropical beach.
Flowering:
No data for this region
Fruiting:
No data for this region
Habitat:
Beaches and marine deltas in tropical areas, where it can form large forests along the coastline, pure or mixed with other species of mangrove trees, called mangrove swamps. Along the Egyptian, Sudanese and Eritrean Red Sea coastline it can form mixed forests with Avicennia marina, the other mangrove tree species from NE Africa.
Distribution:
Indian Ocean, in Africa from the SE of Egypt to Durban (South Africa), reaching towards the E to the island of Okinawa and northern Australia.
Conservation status:
A relatively common and widespread species but with a marked decline in populations. It is not considered threatened at a global level but in North Africa it is a species with a small distribution and with very few specimens. It is listed at a global level in the IUCN Red List of Threatened Species as Least Concern (LC) (Duke et al. 2010). In the Red List of vascular plants of Egypt (Flora Aegyptiaca Vol 1, 2000) it is listed as “Endangered”.
