Macaranga auriculata (Merr.) Airy Shaw

Small tree up to ca. 23 m tall and 30 cm dbh, reproductive from 5 m tall and 2 cm dbh. Twigs solid, glabrous to densely hairy (simple hairs only). Stipules needle-like, crowded at the twig apex, semi-persistent, 2-5 mm long by 0.5-1.5 mm wide. Petioles glabrous to densely hairy, up to 6 cm long. Leaves alternate, elliptic to slightly obovate, 9.5-18 cm long by 3-6 cm wide, length/width-ratio 2.5-3.66, penniveined; secondary veins 8-12, not ending in the margin; leaf base usually slightly cordate to auriculate; leaf upper surface glabrous, sometimes hairy on veins, with 2-4 basal nectary glands on basal veins; leaf lower surface glabrous to hairy on veins, not or sparsely gland dotted, roof-like domatia present between midrib and secondary vein axils. Staminate inflorescences not branched; flowers clustered per bracteole; bracteoles with entire margin. Pistillate inflorescences not branched; fruits 12-15 mm wide, 2-locular, with spines.

Ecology: Occurring up to ca. 1100 m altitude. A typical shade-tolerant forest understorey species. Mainly found in closed primary and secondary forests.

Distribution: China (Hainan), Indochina, Thailand, Peninsular Malaysia, Borneo, Philippines. In Borneo it has been collected in Sarawak, Sabah, West-, Central- and East-Kalimantan.

Notes: Originally this species was described as Mallotus auriculatus Merr. by Merrill (1912) and transferred to the genus Macaranga by Airy Shaw (1965). Subsequently, Airy Shaw (1975) synonymised this species with Macaranga lowii King ex Hook.f. var. lowii. However, Macaranga auriculata differs distinctly and consistently from this species by being not or only sparsely gland dotted on the lower leaf surface (as opposed to densely gland dotted), by the presence of roof-like domatia on the lower leaf surface (as opposed to no domatia), and by the usually more than 2 basal nectary glands on the upper leaf surface, placed some distance from the petiole insertion (as opposed to only 2 basal nectary glands, placed directly next to the petiole insertion). For this reason I decided to treat this species separately here.