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
1. Machaerium lunatum (L.f.) Ducke, Arch.
Jard. Bot. Rio de Janeiro 4: 310. 1925.
Fig. 106. G-L
BASIONYM: Pterocarpus lunatus L.f.
SYNONYM: Drepanocarpus lunatus (L. f.) G.F.W. Meyer
Escambrón, Palo de hoz
Scandent shrub attainig 15 m in length. Stems
cylindrical, attaining up to 12 cm in diameter,
with numerous persistent, recurved stipular
spines. Leaves imparipinnate; leaflets 5-7,
alternate or rarely opposite, 2-7 × 0.5-3 cm, oblong
or oblanceolate, chartaceous, glabrous, the apex
retuse, the base obtuse or rounded, the margins
entire; petiolules 2-3 mm long; stipules recurved,
spiniform, up to 1 cm long. Inflorescences of
axillary or terminal racemes, with few to many
13. MACROPTILIUM
flowers, 5-15 cm long; bracts minute, persistent.
Calyx 3.5-5 mm long, glabrous; corolla pink to
violet-pink, the standard up to 8 mm long, retuse,
the wings falcate, the keel incurved. Legume 2-
3.7 cm wide, in the form of a half-moon, circular
in outline, indehiscent. Seed 1, reniform.
Phenology: Collected in flower from February
to August and in fruit from March to December.
Status: Native, common.
Distribution: In the coastal swamps that border
on the mangroves. Also on Vieques, St. Croix, St.
John, and St. Thomas; Hispaniola, the Lesser
Antilles, tropical continental America and tropical
Africa.
Public Forest: In all probability, found in
Piñones.
Erect, creeping, or clambering herbs or herbaceous vines. Leaves trifoliolate; stipules and stipels
minute. Inflorescences of axillary pseudoracemes, the flowers grouped in pairs on the swellings along
the rachis; bracts minute. Calyx almost campanulate or tubular, of 5 equal or unequal sepals; corolla
usually cardinal red, the standard rounded, reflexed, narrowed at the base, the wings narrowed at the
base, much longer than the other petals, the keel narrowed at the base, twisted in the distal portion,
fused to the staminal tube; stamens 10, diadelphous; ovary superior, subsessile, flattened, pubescent,
with many ovules, the style thickened at the base, twisted, the stigma punctiform. Legume linear,
cylindrical, dehiscent by valves that twist on drying; seeds numerous, small, oblong-cylindrical. A
genus of 20 species, native to the New World.
Key to the species of Macroptilium
1a. Twining vine; terminal leaflet usually trilobate; lower surface densely white-pubescent; corolla
purple ……..……………………………………………..…..................... 1. M. atropurpureum
1b. Erect or clambering herb; terminal leaflet not lobed; lower surface puberulent; corolla maroon,
pink, or white …………………………………….………...……........... 2. M. lathyroides
1. Macroptilium atropurpureum (DC.) Urb.,
Symb. Antill. 9: 457. 1928.
Fig. 107. A-D
BASIONYM: Phaseolus atropurpureus DC.
Herbaceous vine, twining, attainig 3-5 m in
length. Stems cylindrical, strigose. Leaves
alternate, trifoliolate; leaflets 2-8 × 1.7-3.5 cm,
coriaceous, upper surface dull, pubescent; lower
surface densely white-pubescent, with prominent
venation, the apex acute or obtuse; terminal leaflet
ovate-rhombic, sometimes bilobate, the base
cuneate; the lateral leaflets asymmetrical,
unilobate, the base cuneate-obtuse; petiolules
slender, white-pubescent; petioles 1-7 cm long,
white-pubescent; stipules subulate to triangular,
white-pubescent, 2.5-3 mm long; stipels subulate,
white-pubescent, ca. 2 mm long. Inflorescences
of axillary pseudoracemes, erect, 13-26 cm long,
the flowers grouped in pairs on the swellings on
the distal portion of the rachis; pedicels ca. 2 mm
long. Calyx tubular-campanulate, green, with a
reddish tonality, strigose-sericeous, 5-7 mm long,
the sepals subequal or unequal, or all of them