Lianas, the branchlets strongly tetragonal, without interpetiolar glandular fields; pseudostipules foliaceous. Leaves 2-foliolate, sometimes with a simple tendril. Inflorescence a terminal panicle. Calyx short, shallowly campanulate, truncate, ± irregularly lobed or split; corolla yellow with purplish to brownish stripes, funnel-shaped, bilabiate, glandular-lepidote outside. Anthers glabrous, the thecae short, divergent to divaricate. Ovary oblong, lepidote; ovules 4-6-seriate in each locule; disk cupular-pulvinate. Fruit an oblong to narrowly oblong capsule, the valves parallel to septum, woody and convex or rather flattened, rugose-tuberculate or lightly and inconspicuously short-muricate. Seeds thin, 2-winged, the wings membranous, whitish to brownish, not sharply demarcated from seed body.
Southern Mexico, Central America, Colombia, Guyana, Suriname, French Guiana, Ecuador, Peru, Brazil, Bolivia; 2 species, both in the flora area.
1. Corolla 15-20 mm long; capsule valves flattened, less than 1 cm thick, the surface slightly and irregularly verrucose-tuberculate ..... M. hyacinthina
1. Corolla 23-37 mm long; capsule valves strongly convex, 1-3 cm thick, the surface conspicuously rugose-verrucose ..... M. prieurei
Mussatia hyacinthina (Standl.) Sandwith, Recueil Trav. Bot. Néerl. 34: 218. 1937. -Tynanthus hyacinthinus Standl., Publ. Carnegie Inst. Wash. 461: 87. 1935.
Liana. Semideciduous to evergreen lowland forests, 50-300 m; Delta Amacuro (Serranía de Imataca), northern Bolívar, Amazonas (Río Mawarinuma). Widespread but rarely collected elsewhere in Venezuela; Mexico, Central America, Colombia, Guyana, Ecuador, Peru, Bolivia. Fig. 396.
Mussatia prieurei (A. DC.) Bureau ex K. Schum., Pflanzenfam. 4(3b): 224. 1894. -Bignonia prieurei A. DC., Prodr. 9: 154. 1845.
Liana. Nonflooded evergreen lowland forests, 100-200 m; Bolívar (mouth of Río Nichare, km 41 south of El Dorado), Amazonas (near Puerto Ayacucho, San Juan de Manapiare). Colombia, Guyana, Suriname, French Guiana, Peru, Brazil, Bolivia. Fig. 397.
This species is not very different from Mussatia hyacinthina, and they are impossible to distinguish vegetatively. Apparently they are allopatric with M. hyacinthina occurring farther north and west and in drier, more seasonal forests. The sterile Mussatia collections from Amazonas included in M. hyacinthina in the Flora de Venezuela are correctly placed in M. prieurei.