Dipterocarpus gracilis Bl., Bijdr. (1825)

Species name meaning 'narrow or thin'.

Anisoptera palembanica Miq.
Dipterocarpus andamanicus (King) Tewary & A.K.Sarkar
Dipterocarpus angustialatus Heim
Dipterocarpus bancanus Burck
Dipterocarpus fulvus Bl.
Dipterocarpus hispidus (non Thw.) F.-Vill.
Dipterocarpus marginatus Korth.
Dipterocarpus pilosus Roxb.
Dipterocarpus schmidtii Heim
Dipterocarpus skinneri King
Dipterocarpus turbinatus var. andamanicus King
Dipterocarpus vanderhoevenii K. & V.
Dipterocarpus velutina Vidal
Dipterocarpus vernicifluus Blanco
Mocanera verniciflua Blanco
Shorea mollis Boerl.

Upper canopy tree up to 50 m tall and 100 cm dbh. Stem with resin. Stipules ca. 50 mm long. Leaves alternate, simple, penni-veined, lower surface and petiole covered with short soft hairs, lamina only slightly folded between secondary veins. Flowers ca. 45 mm in diameter, whitish-yellow?, placed in racemes. Fruits ca. 20 mm long, red-green?, with two ca. 140 mm long wings placed on top of the nut, wind dispersed.

Twig, leaf bud, stipule outside, leaf beneath, midrib above and petiole densely persistently scabrid rufous tomentose. Twig c. 3 mm diameter apically, terete or slightly compressed, with minute cracks initiating from elongated lenticels. Bud 10-14 by 3-5 mm, narrowly conical, obtuse. Stipule c. 5 cm long, narrowly lanceolate. Leaves 8-15 by 4-10 cm, elliptic to ovate, base obtuse; apex shortly acuminate; nerves 12-20 pairs, usually dense, at 40-50 degrees: petiole 2-2.5 cm long. Raceme to 9 cm long, terminal or axillary, terete, shortly pale brown tomentose or glabrescent, singly branched. Flower bud to 25 by 8 mm. Calyx and corolla typical, calyx shortly tomentose. Stamens c. 30, exceeding the style; filaments short; anthers linear; appendage to connective c. 2 times length of anther, filiform, tapering, sparsely setose. Ovary ovoid-conical, tapering into the stylopodium; stylopodium and style slender, filiform, tomentose in the basal half. Fruit calyx glabrous; tube to 2 cm diameter, smooth, globose; 2 longer lobes to 14 by 2.5 cm, narrowly spatulate, obtuse, to 1 cm broad at base; 3 shorter lobes to 2.2 by 1 cm, ovate, constricted at base, the 2 sides becoming revolute back to back. [from Flora Malesiana]

In undisturbed mixed dipterocarp and seasonal forests up to 1200 m altitude. Can be found throughout the forest, from alluvial sites to dry hillsides and ridges. Also found on limestone.

The timber is commercially harvested.

Andaman Islands, Birma, Thailand, Peninsular Malaysia, Sumatra, Java, Borneo, Philippines.

Local names
Borneo: Damar kumbang, Kaladan, Keruing, Keruing kesat, Keruwing daun kecil, Kruwing, Pudan, Tempurau.
Java: Wuluk bulan.
Malaysia: Keruing kesat, Keruing bungoh, Keruing daun halus.
Philippines: Agan-an (Bicol.), Duha (Ibn.), Kurimau (Ibn.), Lalian (Tag.), Lanutan (Neg.), Lauan (Zamb., Sul.), Pagsa hingau (Tag.), Palemopang (Tag.), Palohap (Sbl.), Pamalalian (Cag., Ibn.), Pamantulen (Ilk.), Pamantuling (Pang.), Pamarnisen (Ibn.), Panao (Tag., Pang., Sbl., Ibn., Pamp.), Putsa hingan (Tag.), Sitam (Ibn.). Sumatra: Bembang.