Vines and Climbing Plants of Puerto Rico and the Virgin Islands

424
Vines and Climbing Plants of Puerto Rico and the Virgin Islands
Slightly woody vine, twining (toward the
right), glabrous, attainig 10 m in length. Stems
flexible, cylindrical, usually with recurved spines.
Leaves opposite, simple, more or less ascendant,
coriaceous, ovate, 7-veined, 6-14 × 5-10 cm, the
apex abruptly acuminate, the base cordiform to
almost truncate, the margins entire, revolute;
upper surface shiny, with the venation slightly
sunken; lower surface dull, with translucent lines,
the primary venation prominent; petioles 4.5-12
cm long, pulvinate at both ends. Inflorescences
axillary, fragrant, unisexual, in pendulous spikes,
the staminate ones fasciculate, the pistillate ones
solitary. Staminate flowers with the perianth 2-
2.5 mm long, the stamens 6, all fertile; pistillate
flowers with the perianth 1-1.5 mm long. Capsule
elliptic-oblong in outline, 1.7 cm long. Seeds with
a basal wing.
Phenology: Collected in flower in July and in
fruit in December.
Status: Exotic, cultivated and escaped from
cultivation, uncommon.
Distribution: In areas of disturbed or
secondary vegetation. Although this species was
described based on material from French Guiana,
it is native to western Africa, where it has been
cultivated for centuries (Burkill, 1985). Today it
is cultivated throughout the tropics, where it has
become naturalized.
Public Forests: Río Abajo.
5. Dioscorea pilosiuscula Bertero ex Spreng.,
Syst. Veg. ed. 16, 2: 152. 1825.
Fig. 175. L-P
Ñame de gunda, Gunda, Dunguey, Air yam,
Wild yam
Non-woody vine, twining, attainig 4-8 m in
length. Stems slender, strong, almost cylindrical
or slightly angular, glabrous or puberulent. Leaves
alternate, 5-7-veined, oblong-ovate or ovate, 5.5-
12 × 2.5-6.5 cm, chartaceous, the apex longacuminate,
the base cordiform, the margins
undulate; upper surface slightly shiny, glabrous,
the venation sunken; lower surface pale green,
dull, with prominent venation, pilose; petioles
slender, glabrous or puberulent, 1.5-4 cm long,
sulcate and with both extremities swollen,
provided with a pair of small ovoid tubercles in
the axil. Inflorescences axillary, pendulous.
Staminate flowers unknown in the populations of
the Antilles; pistillate flowers with the perianth
1.5-2 mm long. Capsule oblong, 1-2.5 cm long.
Seeds ca. 8 mm long, with a basal wing.
Phenology: Flowering and fruiting from
December to July.
Status: Native, uncommon.
Distribution: Uncommon in disturbed areas
of secondary vegetation, in moist zones at lower
and middle elevations. Also on St. John, St.
Thomas, and Tortola; throughout the Antilles and
South America.
Public Forests: El Yunque, Guajataca, and Río
Abajo.
6. Dioscorea polygonoides Humboldt &
Bonpland ex Willd., Sp. Pl. 4: 795. 1806.
Fig. 176. A-I
Gunda
Non-woody vine, twining, attainig 8 m or
more in length. Stems glabrous, more or less
cylindrical. Leaves alternate, ovate, 7-11-veined,
chartaceous or membranaceous, (4)8-21 × (2.7)5-
17 cm, the apex acuminate, the base cordiform;
upper surface shiny, the venation slightly
prominent; lower surface dull, the venation
prominent; petiole 5-8 cm long, the base
marginate, not extended like a pseudostipule;
bulbils angular, up to 5 cm wide, smooth.
Inflorescences axillary, pendulous; the staminate
ones solitary or in pairs, simple or sometimes
branched, up to 50 cm long, with the flowers
grouped in sessile lateral cymes; the pistillate ones
simple, up to 30 cm long, with the flowers solitary.
Flowers minute, sessile, white or pale green;
staminate flowers with the perianth ca. 1 mm
long; fertile stamens 3; pistillate flowers with the
perianth ca. 1 mm long and the hypanthium ca. 2
mm long. Capsules 3-winged, 2.5-3.2 cm long,
in a position almost perpendicular to the rachis
of the spike. Seeds 2 per locule, almost circular,
ca. 5 mm in diameter.
Phenology: Flowering and fruiting throughout
the year.
Status: Native, rather common.
Distribution: In forests of secondary
succession, at middle elevations. Also throughout
the Antilles and tropical America.
Public Forests: El Yunque, Maricao, and Río
Abajo.