Castanopsis motleyana King, Ann. R. Bot. Gard. Calc. 2 (1889)

Synonyms
Castanopsis pearsonii Merr.

Diagnostics
Tree with buttresses and roughly fissured and flaking bark. Twigs densely hairy when young. Stipules ca. 9 mm long. Petiole up to 1.5 cm long, hairy. Leaves alternate, simple, up to 23 by 10 cm, penni-veined, with 14-18 secondary veins, glabrous to densely hairy and brownish coloured below. Male flowers ca. 2 mm diameter, white-yellowish, placed in racemes. Fruits ca. 35 mm long, green-yellow-brown, nut completely enclosed by spiny cupule, splitting irregularly or in four parts, spines c. 1.5 cm.

Description
Tree, 10-42 m by 20-70 cm diameter; buttresses up to 3-4 m tall, 1-2 m out, 5-10 cm thick, spreading; bark rougn, fissured or flaky, chocolate- or reddish brown, branchlets when young with dense fulvous indumentum of longer and mostly also shorter bundle-hairs, glabrescent, slender to sturdy; terminal bud ovoid-ellipsoid, 5-10 by 3-5 mm, scales ovate- or linear-acute, 4-5 by 1-2 mm. Stipules ovate-acute, 7-10 by 3 mm. Leaves thick-coriaceous, (7-)15-23(-32) by (2.5)7-10(-16) cm (index 2-2.8(-3.5)), widest at the middle to sometimes above; base attenuate-acute, top acute with a small sharp acumen; above variable in colour and shine, when young sometimes near the nerves sparsely set with simple or 2-3-fid bundle-hairs which leave a pit when disappeared, underneath dull brown, glabrous to densely set with stellate scales (magnification 30-60!), and/or simple or 2-3-fid bundle-hairs; midrib and nerves strongly prominent beneath, slightly so above; nerves (11-)14-18(-21) pairs at an angle of (50-)70-80 degrees, mostly parallel, ascending, arcuating and anastomosing near the margin; reticulation coarse, dense, subscalariform, distinct beneath; petiole (0.5-)1-1.5(-2.5) cm, hairy as the twig, adaxially flat. Male rachis 10-20 cm, 2-3 mm diameter; bracts and bracteoles membranous, ovate-acute, 10 by 7 mm; male flowers in clusters of 3-7, perianth 4-6-lobed, the lobes acute, 1-1.5 by 0.7-1 mm, densely yellowish brown stellate-tomentose; stamens 10- 12, filaments 2-2.5 mm, anthers 0.2-0.25 mm long, pistillode rounded-triangular, 1.5 mm diameter. Female rachis 15-25 cm, 3-5 mm diameter; bracts and bracteoles thick-coriaceous, ovate-acute, 1 by 0.7 mm; female flowers in clusters of 3, perianth 6-lobed, the lobes 0.7-1 by 0.3-0.6 mm, with dense stellate tomentum on both surfaces; staminodes 12, rudimentary; styles 3, conical, recurved, 1-1.5 mm. Young infructescence 10-20 cm, rachis 3-5 mm diameter, carrying 10-25 young fruits. Young cupule sessile, depressed-globose, with short, sharp, slender and or flat sturdy spines pointing to all directions. Ripe cupule ellipsoid-globose, 3-4 cm through, sometimes flattened adaxially and asymmetrical; wall densely hairy both outside and inside, 3-4 mm thick, densely set with spines 0.5-l.5 cm long and densely fulvous or golden puberulous (magnification 10!), their top glabrous, of a slender, straight kind and in bundles, and/or of a sturdy kind like trees with recurved branches; dehiscence into 4 segments or irregular. Fruit ovoid-conical, 2-2.5 by l.5-2 cm, the scar covering 0.25 part, flat or convex, the free part densely yellowish brown tomentose, top acute; wall 1 mm thick; cotyledons flat-convex. [from Flora Malesiana]

Ecology
In undisturbed mixed dipterocarp forests up to 500 m altitude. Mostly on ridges and hillsides, but also on alluvial sites and along rivers. On ultrabasic to sandy soils.

Distribution
Borneo, Philippines.

Local names
Borneo: Babayi, Berangan, Berangan duan besar, Kulit.