Description

Key Characters:

Growth Form: Shrub or treelet, 1.8–1.9 m tall.

Stems: Stems usually branched, 6–8 mm in diameter, erect or ascending, light gray or brown, unarmed, glabrous, with numerous helically arranged leaf scars toward apex, latex white, viscous.

Roots:

Leaves: Leaves simple. Alternate, scattered along distal portion of stem. Blades lanceolate, 15–30 cm long, 4–9 cm wide. Apex acuminate. Base truncate, rounded, or obtuse. Surfaces glabrous, blades fleshy when fresh, membranous to somewhat chartaceous when dry. Margins serrulate. Pinnately veined. Petioles terete (cylindrical), 9.0–14.5 cm long, ½–¾ as long as lamina. Stipules absent.

Flowers: Flowers in inflorescences several per stem, axillary, racemose, anauxotelic, racemes 5–11–flowered; peduncle and rachis ascending or spreading, glabrous, peduncle 4–10 mm long; rachis 4–13 mm long; bracts 0.5–0.9 mm long, pubescent, triangular or deltate (rarely becoming larger, foliaceous, oblanceolate), persistent, each subtending a pedicel; pedicels 7–11 mm long, ascending or spreading, ebracteolate or with a pair of minute knob-like glabrous or commonly pubescent bracteoles at or above the base; hypanthium 8–10 mm long, 4–5.5 mm in diameter, 1/8–1/6 as long as corolla, narrowly ellipsoid. Flowers tetracyclic, bisexual (perfect), complete, protandrous, epigynous, resupinate, pedicellate. Calyx synsepalous, actinomorphic; lobes 0.5–1.0 mm long, 0.6–1.0 mm wide, pubescent; 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 58–62 mm long, white, sympetalous, zygomorphic, bilabiate, glabrous; tube 30–38 mm long, 2.3–3.3 mm tall at base, 8.0–8.5 mm tall above middle, strongly curved or arcuate, laterally compressed, tallest above the middle, dorsally cleft to about the middle, with a single dorsal knob at thw terminus of the cleft; lobes 5, linear triangular, valvate, spreading, equaling or shorter than the tube (rarely somewhat longer), acute or acuminate at apex, dorsal lobes 20–28 mm long, 2.5–3.5 mm wide, ½ as long to almost as long as tube; ventral lobes 15–21 mm long, 2.5–3.0 mm wide usually connate for ¼–1⁄2 their length. Stamens 5, syngenesious, antisepalous, exserted, emerging from the corolla above (rarely between) the dorsal lobes; filament tube 52–64 mm long; filaments connate, free from the corolla, inserted on the rim of the hypanthium; anther tube 2.3–2.6 mm in diameter, glabrous; anthers connate, dithecal, dehiscing introrsely and longitudinally, 1/8-2/3 as long as the filament tube, dorsal anthers 7–8 mm long, 1/8–⅐ as long as filament tube, occluding the orifice of the tube, with a triangular scale of concrescent hairs 0.4–0.6 mm long at apex, ventral anthers 4.8–6.0 mm long, with tufts of hairs 2–3 mm long at apex. 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: Fruits not seen. Seeds not seen.

Ploidy:

Habitat: Wet to mesic forests.

Elevation Range: 550–640 m.