Author: Prain
Morphological description
Large trees, to 40 m high and 90 cm diameter at breast height; twigs pale or greyish to dark brown, lenticellate, hairy when young.
Leaves imparipinnate, incl. petiole up to 5 cm long; petiolules 3-4(-7) mm long. (kunstleri v trif Dialium CToS35 ) Leaflets 3-5(-7), compound leaves often mixed with unifoliolate ones, elliptic, elliptic-oblong or ovate to lanceolate, (4-)5-15(-19) by (2-)3-6(-7.5) cm, coriaceous; apex long acuminate to acute; base cuneate or rounded; surfaces concolorous, dark brown when dry, glabrous above, glabrescent beneath; nerves (5-)6-8(-9) pairs, sharply arcuating towards apex, rather distinct.
Inflorescence : Panicles usually axillary, mostly in few fascicles, rarely terminal, rachis (4-)6-12(-20) cm, sparsely hairy; pedicels (2-)3-4 mm long. Sepals 3, elliptic-oblong, c. 3.5 by 2-2.5 mm, minutely hairy inside. Stamens 6; filaments 1-1.5 mm long; anthers linear, 3-3.5 mm long, sometimes hairy along both sides of the connective. Ovary c. 1.5 mm long, whitish hairy; style 1.5-2 mm, slightly recurved at apex.
Fruits broadly ellipsoid to ovoid, 3-4 by 2.5-3 cm, mucro sometimes persistent; pericarp rather thick and firm, exocarp glabrescent with age (kunstleri v trif Dialium CToS35 ).
Seeds (sub)orbicular, flattish, c. 1.5 by 1 cm, testa chocolate brown to blackish.
Distribution
Malesia: Peninsular Malaysia, Borneo.
Key to the varieties
a. Leaflets 5, sometimes together with 3 or very rarely 7 in leaves on the same twig, (4-)5-12(-17) by 2-5(-6.5) cm, with the nerves prominent but not distinctly raised beneath Dialium kunstleri kunstleri
b. Leaflets 3 (kunstleri v trif Dialium CToS35 ), often together with unifoliolate leaves on the same twig, (5-)6-15(-19) by (2-)3-6(-7.5) cm, nerves very distinctly raised beneath
Dialium kunstleri trifoliatum
a. Dialium kunstleri Prain var. kunstleri
Morphological description
Leaves: leaflets 5, sometimes together with 3 or very rarely 7 in leaves on the same twig, (4-)5-12(-17) by 2-5(-6.5) cm, with the nerves prominent but not distinctly raised beneath.
Distribution
Malesia: Peninsular Malaysia (seemingly rare), Borneo (very common).
Habitat
Primary forest, altitude 30-250 m, in Sarawak also (once) collected in kerangas forest.
Ecology
Flowering in May, November; fruiting in June, October-November.
b. Dialium kunstleri Prain var. trifoliolatum (de Wit) Rojo
Morphological description
Leaves: leaflets 3, often together with unifoliolate leaves on the same twig, (5-)6-15(-19) by (2-)3-6(-7.5) cm, nerves very distinctly raised beneath.
Distribution
Malesia : Peninsular Malaysia, Borneo.
Habitat
Primary forest, altitude 30-250 m, in Sarawak also (once) collected in kerangas forest.
Ecology
Flowering in May, November; fruiting in June, October-November.