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Ploiarium elegans Korth.

Family Name: Bonnetiaceae
Synonyms: Ploiarium alternifolium
Common Name: Cicada Tree, Riang Riang, Reriang, Kayu Kuat (Kuat Kuat), Keriang, Sesudu Paya
Full Sun: 6-8h Lots of Water Moderate Water Native to Singapore Roadside Tree / Palm Ornamental Flowers Ornamental Foliage Aquatic &Hydrophyte Woody Tree


Family Name
Genus Epithet
Species Epithet
Name Authority
Name Status (botanical)
Common Names

Classifications and Characteristics

Plant Division Angiosperms (Flowering Seed Plants) (Dicotyledon)
Plant Growth Form Shrub (Woody), Tree (Small (6m-15m)), Aquatic & Hydrophyte (Waterside / Marginal)
Lifespan (in Singapore) Perennial
Mode of Nutrition Autotrophic
Maximum Height 15 m


Native Distribution Indochina, Peninsula Malaysia, Singapore, Sumatra, Borneo, Singapore
Native Habitat Terrestrial (Secondary Rainforest, Riverine, Mountain, Freshwater Swamp Forest, Disturbed Area / Open Ground)
Preferred Climate Zone Tropical, Sub-Tropical / Monsoonal
Local Conservation Status Native to Singapore (Common)

Description and Ethnobotany

Growth Form It is a woody shrub or small tree typically growing up to 15 m. Plants growing in the river usually grow up to 0.3 m, while those growing in swamps on peaty soil can reach up to 30 m in height.
Roots When grown in swamps, large numbers of thin stilt roots emerge from the trunk to help anchor the tree in the soil. The roots can begin to grow on the trunk up to 2m above ground.
Foliage Its alternate, stalkless leaves have fleshy, shiny leaf blades that are 5–11.5 by 1.3–4 cm, with scarcely visible veins. The leaf margin is pink and lined with small teeth (serrulate). Leaves are densely arranged in a spiral formation along the branches.
Flowers Its 2.5–3 cm-wide star-shaped flowers have pink tinged green sepals, and pink-tipped white petals.  The flowers possess a green stigma that splits into 5 parts at the tip and have numerous yellow stamens. The petals are approximately egg-shaped and curled slightly inwards along the margin.
Fruits Its elongate-ovoid fruits are 5-valved capsules that turn dark purple when ripe, 1.5–2 cm long and contain many tiny, slender and elongate seeds that are released when they split open lengthwise like an umbrella when ripe.
Habitat It grows in rocky rivers, secondary forest, swamp forest, and occasionally on mountain tops. In Singapore, this species is also found in adinandra belukar (secondary forest on degraded soil, dominated by tiup tiup, Adinandra dumosa).
Associated Fauna Its flowers are pollinated by insects.
Cultivation It can be propagated by seed or stem cutting.
Ethnobotanical Uses Medicinal ( A decoction of the leaves and roots is used in treating stomachache.)
Timber & Products ( Its durable and very strong timber is used in making fence- and house-posts, or floor and roof supports.)

Landscaping Features

Landscaping It is suitable for streetscapes, parks and gardens for its attractive cherry-blossom like flowers.
Desirable Plant Features Ornamental Flowers, Ornamental Foliage
Plant & Rootzone Preference - Tolerance Poor Infertile Soils, Waterlogged Soils (Drains Site), Moist Soils, Well-Drained Soils, Fertile Loamy Soils
Landscape Uses General, Roadside Tree / Palm, Parks & Gardens, Riverine, Marsh / Bog
Thematic Landscaping Water Garden, Marsh Garden

Fauna, Pollination and Dispersal

Pollination Method(s) Biotic (Fauna) (Insects (Bee), Insects (Butterfly, Moth))
Seed or Spore Dispersal Abiotic (Explosive Dehiscence)

Plant Care and Propagation

Light Preference Full Sun
Water Preference Moderate Water, Lots of Water
Maintenance Requirements Moderate
Propagation Method Seed, Stem Cutting


Foliage Retention Evergreen
Mature Foliage Colour(s) Green
Mature Foliage Texture(s) Glossy / Shiny, Smooth
Foliar Type Simple / Unifoliate
Foliar Arrangement Along Stem Spiral
Foliar Attachment to Stem Sessile
Foliar Shape(s) Non-Palm Foliage (Obovate, Oblong)
Foliar Margin Serrulate
Foliar Apex - Tip Acute
Foliar Base Attenuate
Typical Foliar Area Microphyll ( 2.25cm2 - 20.25 cm2 )
Leaf Area Index (LAI) for Green Plot Ratio 40 Tree Dense Canopy
Prominent Young Flush Colour(s) Remarks Green with reddish-pink margins

Floral (Angiosperm)

Flower & Plant Sexuality 1 Bisexual Flowers
Flower Colour(s) Pink, White
Flower Texture(s) Smooth
Flower Grouping Cluster / Inflorescence
Flower Location Terminal
Flower Symmetry Radial
Individual Flower Shape Stellate / Star-shaped
Flower Size - Width 2 cm
Flowering Habit Polycarpic

Fruit, Seed and Spore

Mature Fruit Colour(s) - Angiosperms and Gymnosperms Brown, Purple
Mature Fruit Texture(s) Smooth
Fruit Classification Simple Fruit
Fruit Type 1 Dehiscent Dry Fruit
Fruit Type 2 Capsule



Yong J, Tan PY, Nor Hafiz Hassan, Tan SN. 2010. A Selection of Plants for Greening of Waterways and Waterbodies in the Tropics. Singapore: Chung Printing . 480 pp.

Image Repository



Master ID 1778
Species ID 3071
Flora Disclaimer The information in this website has been compiled from reliable sources, such as reference works on medicinal plants. It is not a substitute for medical advice or treatment and NParks does not purport to provide any medical advice. Readers should always consult his/her physician before using or consuming a plant for medicinal purposes.
Species record last updated on: 14 September 2020.