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. HYLOCEREUS
Lianas, climbing by adventitious roots, with numerous lateral branches. Stems green, angular, with
3 or 4 prominent longitudinal ribs. Leaves absent; areoles surrounded by conical spines along the
margin of the ribs. Flowers bisexual, actinomorphic, solitary, sessile, usually at the ends of the branches;
outer tepals scale-like; inner tepals petaliferous; stamens numerous, the filaments shorter than the
perianth; ovary inferior, forming an elongate, infundibuliform hypanthium, the style elongate, not
exserted, the stigmas numerous, filiform. Fruit a berry with persistent tepals; seeds numerous, minute.
A Caribbean genus of about 20 species.
Key to the species of Hylocereus
1a. Stems with 3 or 4 longitudinal ribs, with the groups of spines on small mounds ..... 1. H. trigonus
1b. Stems with 3 longitudinal ribs, forming a depression in the areas where the groups of spines are
borne ...............................................................................................................................2. H. undatus
1. Hylocereus trigonus (Haw.) Saff., Annual Rep.
Board Regents Smithsonian Inst. 1908: 553.
1909.
Fig. 54. A-C
BASIONYM: Cereus trigonus Haw.
Pitahaya, Chickenet, Strawberry pear
Much branched vine, which climbs by aerial
roots and attains 10 m in length. Stems fleshy,
1.4-2 cm wide, lenticellate, triangular, with 3 or
4 prominent, undulate, longitudinal ribs, with a
group of spines on each of the protuberances that
are found along the margin; spines conical, 4-7
mm long, grayish or brown, usually in groups of
8. Flowers solitary, pendulous, 20-24 cm long,
axillary to the group of spines or terminal on the
branches; perianth infundibuliform; outer tepals
fleshy, green, the basal ones ovate, ca. 2 cm long,
the distal ones oblong, 3.5-7.5 cm long, the inner
tepals white, turning yellowish when mature.
Berries ovoid, pink-purple, 12-14 × 5-7 cm, with
tepals of the hypanthium persistent; seeds
numerous, minute, black, covered with a white
gelatinous matrix.
Phenology: Flowering and fruiting from July
to December.
Status: Native, very common.
Distribution: In dry forests or coastal thickets.
Also on Culebra, Vieques, St. Croix, St. John, St.
Thomas, Tortola, and Virgin Gorda; Hispaniola.
Public forests: Ceiba, Guajataca, Guánica, and
Río Abajo.
2. Hylocereus undatus (Haw.) Britton & Rose in
Britton, Fl. Berm. 256. 1918.
Fig. 54. D-E
BASIONYM: Cereus undatus Haw.
Pitahaya
Much branched vine, creeping or climbing by
aerial roots, attaining 7 m in length. Stems fleshy,
2-5 cm wide, trigonal, with 3 longitudinal ribs
with undulate margins, with depressions in which
are found groups of 1-5 subconical brown spines,
3-4 mm long. Flowers solitary, up to 30 cm long,
axillary to the group of spines or terminal on the
branch; perianth glabrous, infundibuliform; outer
tepals greenish yellow, sometimes with a reddish
tinge, those of the hypanthium ovate-lanceolate,
the distal ones linear-lanceolate, the inner tepals
petaliferous, white, longer than the outer ones;
stamens yellow; inserted; stigmas greenish yellow.
Berry red, ellipsoid, fleshy, 6-12 × 5-7 cm, with
persistent tepals; seeds numerous, minute, black,
covered with a red pulp.
Phenology: Flowering from July to September
and fruiting from September to December.
Status: Exotic, uncommon, cultivated and
naturalized.
Distribution: Cultivated from the coast to the
Cordillera Central, naturalized in dry or coastal
areas. Native to Mexico, but widely cultivated in
the tropics. Also on St. John and St. Thomas.
Public forest: Guánica.