Gonolobus

Vines, herbaceous [woody], perennial; latex white, rarely clear. Stems twining, unarmed, eglandular-pubescent or mixed eglandular- and glandular-pubescent. Leaves deciduous [per­sistent], opposite, petiolate; stipular colleters 2, 1 borne at base of petiole on each side, inter­petiolar colleters absent [present], infrapetiolar colleters absent; laminar colleters present. Inflorescences extra-axillary, racemiform [paniculiform, umbelliform], pedunculate. Flowers: calycine colleters present [absent]; corolla white, light yellow, uniformly green, olive-green, yellow-green, or neon green or multicolored and generally dark maroon or brownish near base and green to yellow-green near tips, rotate, aestivation dextrorse; corolline corona ± annular, sometimes interrupted and developed only in staminal [rarely interstaminal] position, or absent; androecium and gynoecium united into a gynostegium adnate to corolla tube; gynostegial corona of fused staminal and interstaminal segments, lobed [unlobed]; anthers adnate to style, dorsal appendage laminar, locules 2; pollen in each theca massed into rigid, horizontally oriented pollinium, pollinia strongly curved, bearing sterile, navicular portion adjacent to translator, pollinia of adjacent anthers joined by translators to common corpusculum together forming pollinarium. Fruits follicles, solitary or paired, moderately to strongly deflexed, green to brown, ovoid, 5-angled, occasionally fewer-angled, smooth to tuberculate, glabrous or pubescent. Seeds obovate, flattened, winged, not beaked, comose, not arillate. x = 11.

Distribution

United States, Mexico, West Indies, Central America, South America, introduced in Africa.

Discussion

Species 100–150 (3 in the flora).

The indumentum in Gonolobus can consist of trichomes of uniform length but more often includes a mixture of long eglandular, short eglandular, and/or short glandular capitate trichomes. Stems, petioles, peduncles, and pedicels may have indumentum in lines or completely around the stalk (ubiquitous).

Selected References

None.

Lower Taxa

Gonolobus arizonicus, Gonolobus suberosus, Gonolobus taylorianus

Key

1	Stem trichomes eglandular only; corolla white or light yellow, campanulate at base, tube 2.9–5 mm; corolline corona absent; pollinia suborbiculate to rhombic; seed distal margins entire.	Gonolobus arizonicus
1	Stem trichomes eglandular and glandular-capitate; corolla uniformly green, olive-green, yellow-green, or neon green or multicolored and generally dark maroon to brownish near base and green to yellow-green near tips, subcampanulate at base, tube to 1.5 mm; corolline corona present; pollinia ovate; seed distal margins dentate.	> 2
2	Pubescence of internodes ubiquitous, not in lines; calyx lobes 0.2–1 mm wide; corolline corona reduced to small mounds opposite anthers, glabrous.	Gonolobus suberosus
2	Pubescence of internodes in 2 lines; calyx lobes 1–2 mm wide; corolline corona a dis­tinctly raised ring, pubescent with unicellular hairs 0.1–0.3 mm.	Gonolobus taylorianus