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Cratoxylum formosum (Jack) Dyer

Family Name: Hypericaceae
Common Name: Pink Mempat, Derum, Mempat, Entemu, Geronggang Biabas, Gerunggung, Kemutul, Kemutun, Mempitis, 越南黄牛木
Full Sun: 6-8h Moderate Water Caterpillar Food Plant Native to Singapore Fruit & Vegetable Roadside Tree / Palm Ornamental Flowers 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 Tree (Big (>30m), Small (6m-15m))
Lifespan (in Singapore) Perennial
Plant Shape Rounded
Maximum Height 10 m to 45 m


Native Distribution South Andaman Islands, south China, Indochina, south Thailand, Sumatra, Malaysia, Singapore, Bangka Island, the Philippines, Borneo, Java, and Sulawesi
Native Habitat Terrestrial (Primary Rainforest, Secondary Rainforest, Monsoon Forest, Freshwater Swamp Forest, Riverine)
Preferred Climate Zone Tropical, Sub-Tropical / Monsoonal
Local Conservation Status 1 Native to Singapore (Endangered (EN))

Description and Ethnobotany

Growth Form It is a medium to large-sized tree up to 45 m tall, but in Singapore, it is 10 m or shorter. Its bark is grey and scaly. The plant is easy to spot when its crown is covered with light pink flowers amidst the new foliage.
Foliage Its opposite, long-stalked leaves have fleshy to papery leaf blades that are usually narrowly to broadly oval, and 3.5–18 by 1–7.6 cm. Its new leaves have reddish-pink leaf blades that mature to green above and greenish below.
Flowers Its faintly fragrant flowers are 1.3–2.5 cm wide, with light pink petals. They are found in clusters of 1–6, in axils of fallen leaves or on bare twigs.
Fruits Its dark brown fruits are ellipsoid, 10–19 by 4–6 mm, and split open into three parts when ripe to release the winged seeds. Up to half of the bases of the fruits are covered by the sepals too. Its brownish seeds are narrowly drop-shaped, 6–7.5 by 2–4 mm, and many per fruit.
Habitat It grows in hill, primary or secondary forests, river edges, swamps, and on clay or sandy soils, up to 1,200 m altitude.
Associated Fauna It is the preferred local food plant for caterpillars of the archduke (Lexias pardalis dirteana). The adult of the archduke lays its eggs singly on the undersides of leaves of the host plant. Its flowers are also insect-pollinated.
Etymology Greek kratos, strength; Greek xulon, wood, referring to the strong timber; formosus, beautiful or handsome, referring to this species’ flowers.
Ethnobotanical Uses Edible Plant Parts (Edible Leaves)
Food (Fruit & Vegetable : The leaves are edible as they are believed to be beneficial for one’s health.)
Medicinal ( Colic and itch is treated by a decoction, and resin from the bark respectively. Skin problems can be treated by applying a pounded mixture of the bark, leaves and coconut oil.)
Timber & Products ( The wood is a commercial source of medium-weight hardwood known as derum. It is used for carving, charcoal, firewood, furniture, house construction, poles and turnery.  )

Landscaping Features

Landscaping The plant has attractive new foliage, and light pink, cherry blossom- like flowers. It is suitable for parks and roadsides. It can be propagated by seeds and stem cuttings. In Singapore, only a very low percentage of the seeds develop into seedlings. The saplings must be handled with caution during transplanting, as this species may have thorny stems. Its tolerance for a wide range of soil moisture conditions makes it suitable for damp to sandy sites.
Desirable Plant Features Ornamental Flowers
Plant & Rootzone Preference - Tolerance Moist Soils, Well-Drained Soils, Fertile Loamy Soils, Heavy Clay Soils
Landscape Uses Roadside Tree / Palm, Parks & Gardens, Small Gardens, Riverine, Shade Providing Tree / Palm
Species record last updated on: 20 April 2020.