Pereskia guamacho F.A.C.Weber

Authority

Leuenberger, Beat E. 1986. Pereskia (Cactaceae). Mem. New York Bot. Gard. 41: 1-140.

Family

Cactaceae

Scientific Name

Pereskia guamacho F.A.C.Weber

Description

Species Description - Tree, 4-8 m tall, or shrub; trunk usually short, l(-2) m high and to 25(-40) cm thick; young trees monopodial, with subverticillate, diffuse branching, sometimes many-stemmed by formation of lateral erect long shoots; bark brownish-gray on trunk, smooth (?), branches with pale brown to reddish-brown, smooth bark with few whitish lenticels; twigs 2-3(-4) mm thick, green to reddish when fresh, pale brown after periderm formation. Wood yellowish; pith conspicuous, 1.2-2 mm in diam. in branches of 1 cm thickness, transverse-laminate. Areoles 2-4 mm in diam. on twigs, 5-7 mm in diam. on branches, forming knob-like spur shoots 35 mm long on older flowering branches and branchlets, accrescent on trunk to ca. 1 cm diam.; tomentum of the areoles pale gray to pale brown, dense and short, consisting of uniseriate, multicellular trichomes l(-2) mm long; additional longer hairs usually in new growth only; areoles producing spines and brachyblast leaves. Leaves of long shoot not differing from brachyblast leaves; brachyblast leaves 1-3(-4) per areole, fascicled in the upper portion of the areole. Leaves variable in shape and size, narrowly to broadly obovate or elliptic, 2-7(-9) x 1-6 cm, average leaves ca. 4 x 2.5 cm; petiole 1-4(-5) mm long and 1 mm broad, appearing shorter and thicker and often indistinct when fresh; leafblade 1-1.5 mm thick when fresh, fleshy, base attenuate; apex shortly acute to acute-acuminate or obtuse with a short triangular point; venation pseudopalmate to pinnate; midrib thickened but not markedly prominent below when fresh; lateral veins (2-)3-4(-5), diverging at angles of (15-)20-40(-45)°, often inconspicuous in fresh leaves. Spines on young twigs 0-2 per areole, porrect, subulate, 5-20 mm long and 0.5-1.0 mm thick, with slightly bulbous thickening at the base, reddish brown to black, bright dark red at base when young (fresh); spines often lacking on flowering twigs and spur shoots; spines 0-5 on branches, spreading, (5-)10-30(-40) mm long, brown to black, becoming gray with age; spines on trunk 50-60 or more, subulate, 3-5 cm long (said to be to 10 cm long, but no specimens seen), 1-1.7 mm thick. Flowers axillary on young and older areoles (spur shoots), solitary or fascicled (23), sessile or nearly so, appearing before the leaves and rapidly falling unless pollinated, flower buds with subcylindrical receptacle ca. 5 mm in diam. including the dense tomentum and appressed receptacular bracts. Flowers perigynous, rotate, 2-5(-6) cm in diam. when fully expanded; receptacle ca. 5 mm in diam., turbinate, receptacular areoles densely silky-tomentose with several rows of trichomes 1-3 mm long, usually masking the receptacle in bud; hairs white to pale brown; receptacular bracts 15-28, linear-lanceolate, very variable in size, the lower and uppermost 1.5-3 x 1 mm, the middle ones 3-5 x 1-2 mm, rarely leaf-like and to 18 x 5 mm, with acute or rounded apex; sepaloids ca. 3-5, obovate, 10-15 mm long, apex acute or obtuse with a point, blade yellowish or flushed with red below; petaloids 10-12, obovate to narrowly obovate, to 25 x 13 mm, with rounded to truncate-emarginate apex; blade yellow, thin and short-lived. Stamens 200-300, spreading, 9-15 mm long, filaments yellow; anthers 1.0-1.4 x 0.3-0.4 mm, yellow, with darker connective. Pollen (9-)12-15-colpate, medium-sized, tectum with perforations and spinules of ca. 1 µm length. Ovary half inferior, with free roof narrowed into the conical style base; locule ca. 2 mm in diam., with shallow floor and roof with conspicuous septal ridges; placentae parietal, in the middle or lower third of the locule at the base of the septal ridges; style ca. 10 mm long; stigma lobes 5-6, ca. 2-3 mm long. Ovules numerous, ca. 0.25 mm long. Fruit globular to obovate, ca. 15-20 mm in diam., green, fleshy, main body formed by the middle portion of the receptacle, hence bearing only to ca. 10 bracts; bracts lanceolate, to ca. 12 x 4 mm, spreading, persistent, or deciduous at maturity; fruit smooth except for the transverse elliptic leaf scars and the sparsely tomentose inconspicuous areoles; umbilicus narrow, filled by the ca. 10 connivent upper bracts surrounding the crumpled, usually persistent flower remnant; fruit wall 2-4 mm thick; locule hollow. Seeds ca. 10-20 or more, reniform, 3.7-4.1 mm long, 2.9-3.4 mm broad and 1.5-1.6 mm thick, strongly flattened and with a peripheral ridge, smooth, black, glossy; hilum low to rather prominent, cream, with central, depressed funicle scar; micropylar end rounded. Seedlings not observed.

Discussion

Type. “Orinoco basin.” No specimen cited. Neotype designation. Venezuela. Bolívar: Ciudad Bolivar and vie. on the Orinoco, 70 m, Feb-Mar 1921 (fl), L. Bailey & E. Bailey 1351 (US). Rhodocactus guamacho (F. A. C. Weber) F. Knuth in Backeberg & Knuth, Kaktus-ABC 97. 1935. Pereskia colombiana Britton & Rose, Cactaceae 1: 17, fig. 11. 1919. Type. Colombia. Magdalena: Santa Marta, Bonda, 50 m, 5 Apr 1898/99 (fl), H. H. Smith 1886 (lectotype, NY; isotypes, BM, BR, E, F, G, GH, L, LE, MICH, MO, P, S, U, UC, US, VT). Rhodocactus colombianus (Britton & Rose) F. Knuth in Backeberg & Knuth, Kaktus-ABC 97. 1935. Local names and uses. Colombia: guamacho. Venezuela: guamacho (Guárico, Mérida, Miranda), supí (Falcón), suspiro (Mérida), suspire, siichi (Zulia). The fruits are edible and the leaves are eaten by cattle. Trunks and larger branches are used for fence posts, which root and grow to considerable size. It is also grown as a hedge. Although Pereskia guamacho was described as late as 1898, specimens of this taxon were the first ones to be collected in pre-Linnean times besides those of P. aculeata. Dillenius (1732) recognized the plant illustrated by Plukenet (1692) as probably different from Plumier’s “Pereskia aculeata flore albo fructu flavescente," but Linnaeus (1753) cited both Dillenius’s plate and that of Commelin (1697, Comm. hort. 1, p. 135, t. 70) under Cactus pereskia. Later monographers evidently failed to pay closer attention to these plates and overlooked specimens in the Sloane Herbarium (BM), which reveal that more than one species was involved in Linné’s Cactus pereskia. Commelin’s plate shows an erect tree-like plant originating from Margarita Island (Nueva Esparta, Venezuela), and Plukenet’s straight-spined plant is also very distinct from the scandent, geminately hooked P. aculeata. Both are in fact P. guamacho. In the 18th and 19th century only a few specimens, unidentified or misidentified, were collected of this species, namely by Mutis in Colombia, between 1760 and 1808, and later by Schott, Plée, and Fendler, antedating Weber’s description. None of these seem to have been known of or seen by Weber, who gives the Orinoco basin as the origin but cites no collector or herbarium specimen with his fairly accurate description of a flowering plant. Leaf shape and size of P. guamacho are variable even on the same plant and the characters on which Britton and Rose based P. colombiana are not reliable, as noted already by Wagenaar Hummelinck (1938).

Distribution

Distribution (Fig. 33) and phenology. Colombia, Venezuela, uncertain in southern Dutch Antilles (Bonaire). From sea level to 800 m, rarely to 1800 m, in dry coastal formations, deciduous seasonal woods, “espinares,” “selvas claras, ‘bosque caducifolio,” flowering mainly from March to May in the leafless condition, at the end of the dry season; fruiting from July to September. The record for Bonaire seems doubtful, as Boldingh (1913) did not mention it and because it was not confirmed b

Colombia South America| Venezuela South America| Bonaire South America|