The plant produces a cluster of flowers that develop into pods. When the
pods ripen, they explode to propel the seeds up to 2m away.
Holly-leaved Acanthus, Holly Mangrove,
Jeruju Putih (Malay)
plants have no relation whatsoever with the Christmas Holly, although
they appear similar.
In fact, not all the leaves have the spiny edges that give them their
common name. Leaves growing the deep shade can be totally spineless.
Unlike some mangrove plants, Sea Holly do not exclude salt at the
root level. In fact, their sap is salty and excess salt is secreted
through the leaves, to be removed by rain or wind. Sometimes, the
salt can be seen as a white crystalline layer on the upper surface.
and wetland wildlife at
Sungei Buloh Nature Park
A shrub that grows to 1.5 m tall.
Roots: May develop small
Leaves: Thick, shiny, waxy,
may have prickly edges.
Flowers: In a cluster at
the branch tip. The species A. ilicifolius has
light violet flowers, while A. ebracteatus has
Fruits: Shiny green pods
in a cluster.
Status in Singapore: Rare.
Found only in suitable habitats, mostly northern parts
of the island.
World distribution: India
to Polynesia and Australia.
Classification: Family Acanthaceae.
Holly grows on mud near the hide tide mark, often on mud
lobster mounds. It can grow equally well under trees and in open areas.
But it grows especially well in areas with more freshwater input. The plant
can sometimes cover large areas and form thickets, particularly in disturbed
mangrove. They also grow along river banks.
Uses: In Indonesia, the entire plant is placed in rice sacks
to keep the rice dry (i.e., acts as a desiccant).
Traditional medicinal uses: The leaves
of A. ilicifolius are used to treat rheumatism, neuralgia and poison
arrow wounds (Malaysia). It is widely believed among mangrove dwellers that
chewing the leaves will protect against snake bite. The pounded seeds of
A. ebracteatus are used to treat boils, the juice of leaves to prevent
hair loss and the leaves themselves to ward off evil (Malay). Both species
are also used to treat kidney stones. The whole plant is boiled in fresh
water, and the patient drinks the solution instead of water, half a glass
at a time, until the signs and symptoms disappear (Thailand). Water extracted
from the bark is used to treat colds and skin allergies. Ground fresh bark
is used as an antiseptic. Tea brewed from the leaves relieves pain and purifies
the blood (widespread in both the Old and New World).
Role in the habitat: Forming the undergrowth
in the back mangroves, Sea Holly provides shelter for small creatures, and
food for those that manage to graze their thorny leaves.
- Ivan Polunin,
"Plants and Flowers of Singapore", Times Editions,
1987 (p. 64: description, habitat, distribution, photo).
- Peter K L Ng and
N Sivasothi, "A Guide to the Mangroves of Singapore I: The Ecosystem
and Plant Diversity", Singapore Science Centre, 1999 (p. 88-90:
description, habit, photo, uses).
- Colin Field, "Journey
among Mangroves", International Society for Mangrove Ecosystems,
1995 (p. 70: medicinal use).
- Michael Mastaller,
"Mangroves: The Forgotten Forest Between Land and Sea",
Tropical Press, 1997 (p. 97: medicinal uses).