33. Haldina Ridsdale, Blumea. 24: 360. 1979.
心叶木属 xin ye mu shu
Authors: Tao Chen & Charlotte M. Taylor
Large trees, unarmed; buds flattened with stipules erect and pressed to each other. Raphides absent. Leaves opposite, decussate, with domatia; stipules caducous, interpetiolar, ovate to oblong, entire. Inflorescences axillary, capitate with 1 or 2(-5) fasciculate globose heads, many flowered, pedunculate, bracteate; peduncles articulate and bracteate near top; bracteoles spatulate to spatulate-clavate. Flowers sessile, bisexual, monomorphic. Calyx limb 5-lobed. Corolla pale to dark yellow, salverform, glabrous inside; lobes 5, imbricate in bud. Stamens 5, inserted in upper part of corolla tube, partially exserted; filaments reduced; anthers basifixed. Ovary 2-celled, ovules numerous in each cell, pendulous on axile placentas attached to upper third of septum; stigma ovoid to subglobose, exserted. Fruiting heads globose, with fruit rather tightly packed. Fruit capsular, obconic to ellipsoid-oblong, septicidally then loculicidally dehiscent into 2 valves separating from base to apex and from persistent septum, cartilaginous to stiffly papery, with calyx limb persistent on persistent septum; seeds numerous, medium-sized, ovoid to fusiform, slightly flattened, shortly winged on ends.
One species: Cambodia, China, India, Nepal, Sri Lanka, Thailand, Vietnam.
Ridsdale (loc. cit.) and Puff et al. (Rubiaceae of Thailand, 52. 2005) described the aestivation of the corolla lobes as, respectively, "valvate but strongly imbricate at apex" and "valvate in bud (but strongly imbricate at the apex)"; they also both describe the fruit as separating into 4 valves, but only 2 valves have been seen on the specimens studied.