Pentasacme pulcherrima A.J.C. Grierson & D.G. Long

Family Description

Woody climbers, shrubs or perenial herbs, sap of white latex usually present. Leaves simple, generally entire, opposite or whorled in bhutanese species; usually with a small group of external nectaries on upper surface of midrib at babe of lamina; stipules minute or absent. Inflorescence cymose often umbellate, sometimes racemose usually axillary. Flowers 5-merous actinomorphic, hermaphrodite. Calyx fused and deeply divided to base. Corolla fused with lobes controted or valvet; tube often with a ring of hairs within; both of either corolla lobes or stamenbearing scales or appendages which form cocorolline and staminal coronas respectievely. stamens inserted at base of coroll; fillaments short to absent; anthers usually fused into a ring forming gynostegium; filaments or back of anthers usually bearing cartilaginous appendages involved in pollination mechanisms. pollen in each half of bilocular anthers usually united into a waxy polliniumOvary superior or partly inferoir, of two carpels united only by style apices; styles two short, each bearing peltate stigma of 5 spreading lobes; carpels containing numerous anatropous in several rows on single adaxial placenta. Fruit a pair of erect divergent follicles, or solitary by abortion. Seeds flattened, ovate to oblong, with deciduous terminal comma of long, silky white hairs.

Genus Description

Tufted, almost glabrous, perennial herbs with numerous arching stems, woody at base. Leaves opposite, in two rows, membranous, subsessile; extrafloral nectaries appearing as a conspicuous black gland at base of pale green leaves. Inflorescence a few-flowered umbellate cyme, sessile, borne between petiole bases of a leaf pair (interpetiolar), one per leaf pair and on alternating sides of stem. Flowers (in Bhutanese species) white, large and showy with long corolla lobes, horizontal at first, becoming pendulous. Corolla tube very short; lobes long and narrow, overlapping to the right; corolline coronal lobes reduced to small oblong appendages on corolla tube. Staminal column very short, anther large, incurved over stigmatic surface; pollen in non-flattened, ovoid, erect, waxy pollinia, one per anther locule; corpusculum golden-brown; translator arms short, horizontal. Stigmatic head conical, concealed by anthers.

Species description

Stems 30-40cm long, little branched. Leaves ovate to ovate lanceolate, 6-13 x 1.6-4cm, apex acuminate to narrowly acute, base cuneat; petiole 2-7mm. Inflorescences 3-5 flowered; pedicels 1-2cm long, slender. Calyx lobes ovate acute, c 2.5mm long. Corolla tube c 1mm long; lobes lanceolate, 20-30 x 2.5-4mm; Corolline coronal lobes c 1.5mm long. staminal colomn c 2mm high; anthers obovate, apex broadly acute. Follicles unknown.