Rubiaceae of the New World

By Piero Delprete and Rocio Cortés
 

HENRIQUEZIA Spruce ex Bentham

Henriquezia nitida, inflorescence      Brazil           Photo  P. Maas

Henriquezia nitida, fruit  Brazil                 Photo P. Maas

Shrubs or medium-sized trees to tall canopy trees; raphides absent; axillary thorns absent. Stipules intrapetiolar, narrowly triangular or deltoid, persistent. Leaves whorled, 3 to 6 per node, long-petiolate; blades elliptic, obovate or oblong, chartaceous or thinly coriaceous; foliar pellucid glands absent; domatia absent. Inflorescence terminal, not frondose; cymose, pauciflorous to multiflorous. Flowers bisexual, protandrous. Calyx cup-shaped, with foliose lobes, caducous; lobes 4, deltoid, small or lanceolate. Calycophylls absent. Corolla broadly infundibuliform, zygomorphic, gibbose at base, pink or red; tube externally pubescent, internally glabrous or puberulent, with or without a pubescent ring at orifice inside; orifice annular thickening absent; lobes 5, imbricate (tube non reduplicate), ovate or oblong, margin entire, truncate, rounded, or acute at apex. Stamens alternate to the corolla lobes, included; anthers elliptic or linear, round at base, acute at apex, dehiscing by longitudinal slits, dorsifixed near the middle; filaments attached at the middle of the corolla tube, free at base, slender, long, shorter than corolla tube, unequal, glabrous. Pollen colporate, apertures 4 to 6, exine surface reticulate, released as monads. Style included, filiform throughout, glabrous; lobes 2, ovate. Ovary inferior, 2-locular, ovoid; placentation axile, placenta peltate on the basal portion of the septum, ovules 4 per locule. Fruit a loculicidal capsule, dehiscing basipetally, thickly woody. Seeds horizontal, large, dorsoventrally compressed; wings concentric with entire margin.

Geographic distribution: Magdalena-Llanos area, western Amazon Basin, Guayana Shield and central Amazon basin.

Number of species: 3.

References: G. K. Rogers, Gleasonia, Henriquezia, and Platicarpum (Rubiaceae). Flora Neotr. Monogr. 39: 1–134. 1984.