Flora of Barro Colorado Island

Calopogonium caeruleum

(Benth.) Sauv., Ann. Acad. Havana 5:337.1869

Vine, to 5 m long, softly orange-tomentose all over. Leaves trifoliolate; stipules inconspicuous, caducous; petioles 3-10 cm long; rachis lacking or to 1.5 cm long; petiolules slightly pulvinate, articulate, ca 5 mm long; leaflets rhombic-ovate, rounded to acuminate at apex, obtuse to slightly subcordate at base, 5-11 cm long, 4-8 cm wide, the veins at base 3, the secondary lateral veins prominulous, perpendicular to primary lateral veins and often extending between pairs of primary laterals. Ra­cemes axillary, 2-40 cm long; flowers in fascicles arising from tubercles 2-8 mm long; bracts subulate, ca 2 mm long; pedicels 1-2 mm long; calyx ca 4 mm long, densely hispid, bilabiate, lobed ca half its length, the upper lip shallowly bifid, the lower lip with 3 linear teeth; petals blue, to 10.5 mm long; standard emarginate at apex, flat and erect, marked at center with green; wings and keel slightly shorter than standard, the wings adhering weakly to sides of keel, the keel fused apically, not enclosing style or stamens; stamens diadelphous, ca 4 mm long; filaments free above from about the middle; style straight, antrorsely hispidulous, almost equaling standard, much longer than anthers; nectar copious, storing in calyx. Legumes narrowly oblong, flattened, acuminate, 3.5-6 cm long, 6-8 mm wide; seeds    4-8, ovoid, ca 5 mm long, reddish-brown. Hladik 136.

Rare; collected only once. Occurring commonly along roadsides and at the edges of clearings in other areas of the Canal Zone. Flowers mostly in January and February (sometimes to March), with the fruits maturing in March and April.

Southern Mexico to northern South America; West Indies. In Panama, known principally from tropical moist forest in the Canal Zone, Bocas del Toro, Chiriqui, Vera­guas, Herrera, Panama, and Darien; known also from premontane moist forest in Herrera and premontane wet forest in Chiriqui.

Photos from STRI Digital Archive

  • Calopogonium caeruleum