Vines and Climbing Plants of Puerto Rico and the Virgin Islands

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Vines and Climbing Plants of Puerto Rico and the Virgin Islands
rounded, mucronate, the base obtuse or rounded,
frequently unequal on the lateral leaflets, the
margins entire; upper surface strigulose; lower
surface sericeous-pubescent, with prominent
venation, ciliate; petiolules tomentose, 2-4 mm
long; rachis ferruginous-tomentose, sulcate, 0.2-
2 cm long; petioles ferruginous-tomentose,
sulcate, 3-11.5 cm long; stipules lanceolate,
pubescent, 3-4 mm long; stipels linear, 1-2 mm
long. Inflorescences of axillary pseudoracemes,
10-15 cm long, with 2 or 3 flowers grouped at the
nodes; peduncle tomentose or sericeous. Calyx
campanulate, ca. 6 mm long, tomentose, the lobes
linear; corolla pink or lavender, the standard ca.
4 mm long, oblong or rounded, the wings longer
21. VIGNA
than the keel, the keel whitish. Legume flattened,
linear, 4-7 × 0.3-0.4 cm, ferruginous-tomentose,
with a curved beak at the apex, dehiscent by valves
that twist back in a spiral. Seeds oblong, 4-5 mm
long, reddish brown.
Phenology: Collected in flower from October
to January and in fruit from October to March.
Status: Native, relatively common.
Distribution: In disturbed areas such as
roadsides, pastures, secondary forests, and
thickets, at middle and lower elevations. Also in
the Greater Antilles, tropical continental America
and introduced in tropical Africa.
Public Forests: Carite, Guajataca, Maricao,
Río Abajo, and Toro Negro.
Herbaceous vines, twining, climbing, or creeping. Leaves alternate, trifoliolate; stipules of various
forms, persistent; stipels subulate. Inflorescences of axillary or terminal pseudoracemes; bracts small.
Calyx campanulate, bilabiate, with 5 lobes, two of which are almost completely united; corolla yellow,
pink, or pale blue, the standard rounded, the wings unguiculate, with a narrow projection or spur at the
base, the keel recurved, as long as the wings; stamens 10, diadelphous, the anthers of the same size;
ovary sessile, with numerous ovules, the style curved, pubescent on the distal portion, the stigma
lateral. Fruit an oblong or linear legume, flattened to cylindrical, dehiscent by valves that twist on
opening; seeds flattened, quadrangular or almost reniform. A genus of about 100 species, the majority
of tropical Africa and Asia.
Key to the species of Vigna
1a. Corolla uniformly brilliant yellow………………………………………………………..2
1b. Corolla pink or violet-pink, changing to white or pale yellow with purplish lines .……..5
2a. Standard ca. 1.5 cm long; legumes 4-7 cm long…………………………………………..3
2b. Standard 6-10 mm long; legumes 1-4 cm long……………………………………………4
3a. Leaflets chartaceous, ovate, acute at the apex; stipules sagittate at the base; legumes 4-7 cm long
..............………………….....…………………………………………..………5. V. luteola
3b. Leaflets fleshy, obovate, obtuse, or rounded at the apex; stipules truncate at the base; legumes 5-6
cm long .........................……………………………………………………….....6. V. marina
4a. Standard ca. 6 mm long; legume 8-15 mm long, with 1-3 seeds …………………. V. hosei
4b. Standard ca. 1 cm long; legume 3-4 cm long, with 5-7 seeds……………....4. V. longifolia
5a. Standard < 1 cm long; legumes ascendant …………..…………………..7. V. peduncularis
5b. Standard 1.5-3 cm long; legumes sparse or pendulous…………………………………….6
6a. Style spirally twisted……………………………………………………………………... 7
6b. Style erect or sigmoid…………………………………………………………………….. 8