Macaranga hullettii King ex Hook.f., Fl. Br. Ind. 5 (1887)
Named after R.W. Hullett [1843 - 1914], a British plant collector.
Synonyms
Macaranga bartlettii Merr.
Macaranga hullettii subsp. borneensis Whitmore
Macaranga hullettii subsp. hullettii
Tanarius hullettii (King ex Hook.f.) Kuntze
Diagnostics
Understorey tree up to 18 m tall and 32 cm dbh. Twigs hollow, ant-inhabited.
Stipules recurved, producing food bodies for ants, ca. 9 mm long. Leaves
alternate, simple, peltate, palmately veined, glabrous. Flowers ca. 0.5 mm
diameter, greenish, placed in bundles within fimbriate bracts which are part of
large branched inflorescences. Fruits ca. 11 mm diameter, green-yellow-reddish,
dehiscent, 4-lobed horned capsules, seeds with pink aril.
Description
Small tree to 18 m tall, but often flowering from as small as 3 m; twigs 5-9 mm in diam.,
usually glabrous or with scattered to dense erect silvery hairs, hollow, housing ants. Bark
smooth, pale grey-brown, hoop-marked. Stipules broadly ovate-elliptic, 5-9 by 5-10 mm, mostly
glabrous or with scattered minute silvery or ferrugineus hairs near the base, light green or
yellowish-brown when fresh rarely darker, recurved and appressed to the stem, the margin usually
slightly upturned in dry specimens, producing food-bodies on the abaxial surface, usually c.
3-4 pairs persistent on the stem. Leaves: petioles terete, 8-20(-25) cm long, mostly glabrous or
sometimes finely silvery pubescent; blades narrowly ovate to ovate, 14-32 by 6-16(-22) cm, unlobed
or tricusped to sometimes trilobed, the lobes usually short and narrowly acuminate, or rarely
dissected to c. 1/3 of the leaf length with ascending sharp lobes, 1-3(-4) cm peltate, rounded
to broadly rounded, margin entire to distantly and prominently serrate with small flattened
nectaries, apex acute to finely acuminate, adaxial surface glabrous or scattered with erect
silvery hairs along the veins and particularly toward the petiole insertion, abaxial surface
usually glabrous or sometimes with fine silvery hairs along the veins, 1st degree venation palmate
with 7-9 prominent veins, 2nd degree venation scalariform and looping near the margins or
terminating at the margin in small protruding nectaries, 3rd degree venation scalariform,
4th degree venation loosely reticulate; young leaves pale to reddish brown, with fine ferrugineus
hairs and sometimes with scattered erect silvery hairs, soon becoming glabrous. Staminate
inflorescences paniculate, erect, 10-30 cm long, light green drying black, glabrous rarely with
a few minute ferrugineus hairs towards the apex, 3(-4) axis orders, basal unbranched axis flattened
and 1/2-3/4 of total inflorescence length, first pair of branches opposite with accessory branches;
bracts ovate-elliptic, 6-13 by 3-6 min, margin entire, apex acute, glabrous or scattered with fine
ferrugineus hairs towards the base, caducous; bracteoles ovate-elliptic, 4-8 by 3-5 mm, margin
entire or often with several lateral narrow teeth, apex caudate, adaxial surface often densely
ferrugineus scaly particularly towards the base, abaxial surface glabrous or scattered with minute
ferrugineus hairs. Staminate flowers 20-35 per cluster, c. 1 mm long, sessile; sepals 3, fused,
splitting to c. 1/4, apex densely covered in minute crisped ferrugineus hairs; stamens 1, anthers
3-locular. Pistillate inflorescences 4-10 by 2-5 cm, unbranched with the flowers/fruits clustered
at the distal end of the axis, or sometimes with one pair of short opposite branches without
accessory branches, usually glabrous or with erect silvery hairs along the basal axis; bracts finely
dissected, caducous. Pistillate flowers 3-5 by c. 2 mm; calyx urceolate, c. 2 mm long, +/- glabrous
or with a few scattered ferrugineus hairs, persistent: ovary (4-)5-carpellate, c. 2 mm long; styles
2-3 mm long, expanding at maturity, fused at the base, free and spreading from c. 2/3 of the length,
persisting to form a prominent 3-5 mm long crown at fruit apex. Fruits subglobose, 6-8 by 10-13 mm,
sessile, one discrete glandular patch on each carpel wall developing into a long slender horn-like
process 4-7 mm long, covered in greenish-yellow, sticky exudate. Seeds ovoid, 4-4.5 mm in diam.,
black, coarsely grooved, encased in a fleshy bright pinkish-red aril. [from Flora Malesiana]
Ecology
In undisturbed to disturbed mixed dipterocarp, keranga and sub-montane
forests up to 1350 m altitude. Usually on alluvial sites and along rivers. Mainly
on rocky to sandy soils, but also on clay. This species is not one of the very high-light demanding
species of Macaranga; it has medium growth and photosynthetic rates, and is often found in partial
shade within primary mixed dipterocarp forests.
Distribution
Peninsular Thailand, Peninsular Malaysia, Sumatra, Borneo.
Local names
Borneo: Menaseng, Purang, Purang karung.
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