Description

Key Characters:

Growth Form: Iteroparous (polycarpic) shrubs, treelets, and palm-like trees up to 9 m tall.

Stems: Stems erect or ascending, light gray or brown, unarmed, glabrous, with numerous helically arranged leaf scars toward apex, latex white, viscous. section Delissia: Stems usually unbranched, (4.5-)14-54 mm in diameter toward apex. section Rhytidospermae: Stems usually branched, 4-14 mm in diameter. section Macranthae: Stems usually branched, 5-20 mm diameter toward apex.

Roots:

Leaves: Leaves simple. Alternate. In section Delissea: leaves in a dense apical rosette. In section Rhytidospermae: leaves scattered along upper portion of stem. In section Macranthae: leaves scattered along distal portion of stem. Surfaces glabrous, blades fleshy when fresh, membranous to somewhat chartaceous when dry. Margins entire or pinnately cleft or parted into 3–7 triangular segments; variously toothed. Pinnately veined. Petiolate; petiole terete (cylindrical). section Delissea: petiole 1/3 as long to as long as lamina. section Rhytidospermae: petiole 1/5-1/2 as long as lamina. section Macranthae: petiole 1/5 as long as to somewhat longer than lamina. Stipules absent.

Flowers: Flowers in inflorescences several per stem, axillary, racemose, anauxotelic, 5–32–flowered; peduncle and rachis ascending or spreading, glabrous; bracts tiny, triangular or deltate (rarely becoming larger, foliaceous, oblanceolate), persistent, each subtending a pedicel; pedicels shorter than the supported flower, ascending or spreading, ebracteolate or with a pair of minute knob-like glabrous or commonly pubescent bracteoles at or above the base. section delissea: bracts pubescent, section rhytidospermae: bracts glabrous. section macranthae: bracts pubescent or glabrous. Flowers tetracyclic, bisexual (perfect), complete, protandrous, epigynous, resupinate, pedicellate. Calyx synsepalous, actinomorphic; tube adnate to the ovary, forming a glabrous hypanthium 1/10–⅓ as long as the corolla; lobes 5, persistent, distinct, triangular or deltate, 1/20–1/2 as long as the hypanthium, glabrous or pubescent. Corolla sympetalous, zygomorphic, bilabiate, white or greenish (sometimes suffused with purple), glabrous; tube curved or arcuate, laterally compressed, tallest above the middle (creating a "hump–backed" appearance in profile), dorsally cleft to about the middle, with a small knob at the terminus of the cleft, sometimes with a pair of additional knobs laterally; lobes 5, linear triangular, valvate, spreading, equaling or shorter than the tube (rarely somewhat longer), acute or acuminate at apex, somewhat dimorphic, the dorsal pair longer, the ventral three usually connate for ¼–1⁄2 their length. section Delissea: Corolla 16-30 mm long, greenish, the tube gently curved, 1.2-4.0 mm tall above the middle, with 1 dorsal and 2 lateral knobs. section Rhytidospermae: Corolla 14-25 mm long, greenish, the tube gently curved, 2.3-4.2 mm tall above the middle, with a single dorsal knob. section Macranthae: Corolla 32-62 mm long, white, the tube strongly curved or arcuate, 3.2-8.5 mm tall above the middle, with a single dorsal knob (rarely a dorsal plus 2 laterals). Stamens 5, syngenesious, antisepalous, exserted, emerging from the corolla above (rarely between) the dorsal lobes; filaments connate, free from the corolla, inserted on the rim of the hypanthium; anthers connate, dithecal, dehiscing introrsely and longitudinally, 1/8-2/3 as long as the filament tube, the dorsal three a little longer than the ventral pair, occluding the orifice of the tube, the surface of the tube glabrous or sparsely pubescent, the ventral pair with apical tufts of stiff white hairs. section Delissea: filament tube 13-24 mm long; anther tube 1.2-2.2 mm in diameter. section Rhytidospermae: filament tube 12-20 mm long; anther tube 1.7-2.0 mm in diameter. section Macranthae: filament tube 29-55 mm long; anther tube 2.0-3.5 mm in diameter. Pollen tricolporate, prolate, ellipsoidal. Ovary inferior, 2-loculed, crowned by an annular nectary; placentae axile; ovules many; style slender, terete (cylindrical), with a ring of stiff white hairs near the apex; stigma 2-lobed, the lobes appressed and non–receptive as the style grows through the anther tube, pushing out pollen, after which the stigmas spread and become receptive.

Fruit: Fruit a small purple fleshy thin–walled berry; globose; cylindric; or ellipsoid; often crowned by a low rim. Seeds numerous; large; grayish white; ellipsoid; compressed; dull; transversely rugose (Type G of Buss et al. 2001).

Ploidy: 2n = 28

Habitat:

Elevation Range: