Cyathocalyx ridleyi (King) J.Sinclair, Gard. Bull. Singapore 14: 237 (1955)

Species named after Henry Nicholas Ridley [1855-?], the first director of the Singapore Botanic Gardens.

Synonyms
Xylopia ridleyi King

Description
A monopodal tree with a tight almost spherical crown supported by a spiral of branches radiating from the main trunk. Twigs with peeling bark and on cross section, with clearly visible rays radiating from the center of the twig, densely hairy when young. Stipules absent. Leaves alternate in one plane, resulting in zig-zag shaped twig, leaves rather large with fat petioles, lower surface whitish and with clearly visible venation. Inflorescences axillary, grouped in bundles on short stalks. Flowers with small outer whorl of three setals, and six extremely elongated petals (this is the main differentiating character with Cyathocalyx ramuliflorus which has short petals), all green coloured. Fruits apocarps with each carpel being sessile, carpels green and round ca. 3 cm diameter.

Ecology
This light loving tree tends to grow quickly towards openings in the crown. Often the trunk may be seen to have many twists and turns, testimony to changing light conditions as the tree grew from sapling. Found up to 1500 m elevation.

Distribution
Peninsular Malaysia, Sumatra, Borneo.

Local names
Singapore: Antoi.