Blepharandra hypoleuca (Benth.) Griseb.

  • Authority

    Maguire, Bassett. 1978. The botany of the Guayana Highland--part XI. Mem. New York Bot. Gard. 32: 1-391.

  • Family

    Malpighiaceae

  • Scientific Name

    Blepharandra hypoleuca (Benth.) Griseb.

  • Description

    Species Description - Shrubs or small trees 1-8 m tall; vegetative stems loosely sericeous, eventually glabrate. Lamina ofthe larger leaves 4.5-15.5 cm long, 3-9.5 cm wide, elliptical or ovate, truncate to deeply cordate at the base, sHghtly revolute at the margin, obtuse or rounded at the apex, coriaceous, green and glabrous above, glaucous and tomentose or sericeous to glabrate below, the glaucescence white and flaky or yellowish and granular, the hairs light brown to dark reddish-brown, usually a mixture of long straight reflexed hairs and short twisted hairs, the vesture varying greatly in abundance and persistence; petiole 2-14(-18) mm long, sericeous or tomentose to glabrate; stipules 5-17(-22) mm long, 3-9 mm wide, ovate or triangular, slightly asymmetrical, acuminate at the apex, free, deciduous before the leaves, often with a prominent midrib, tomentose on both sides and ferrugineous-hirsute adaxially. Inflorescence a terminal, simple or rarely ternate thyrse or pseudoraceme 5-20 cm long, densely and persistently villous or velutinous, the hairs light to dark brown; bracts 5-11 mm long, 2-3 mm wide, narrowly triangular, flat or navicular, entire or denticulate, abaxially villous or sericeous, adaxiallly glabrous, caducous; cincinni (1-)2-5-flowered, the primary peduncle (0-)2-12 mm long, villous or velutinous; bracteoles 2-7 mm long, 0.5-3 mm wide, linear to ovate, flat or slightly concave, entire or denticulate, abaxially villous to subglabrous and ciliate at the margin, adaxially usually glabrous, caducous or variably persistent. Pedicel 5-10(-16) mm long, villous or velutinous. Calyx with the glands 1-2 mm long, green or pink, circular or elliptical or obovate, often free at the apex, rarely rudimentary, the sepal lobes 2.5-4.5 mm long, 1.5-3 mm wide, triangular, revolute, entire or denticulate, abaxially tomentose or villous, adaxially glabrous or proximally tomentose, slightly accrescent in fruit (up to 5 mm long). Petals glabrous or with a few hairs at base of claw, erose or denticulate, the lateral 4 white, with the claw 1.5-2.5 mm long and the limb 3.5-5(-7) mm long and 4-5.5(-7) mm wide, subcircular, flat or concave, the posterior petal yellow or white, with the claw 2-3 mm long and the limb 4-5.5(-7.5) mm long and 4.5-6(-7.5) mm wide, concave or galeiform. Filaments 2-4 mm long, densely hirsute, especially at the base; anthers 1.3-2.5 mm long, each locule bearing many (rarely few) basifixed hairs (0.5-)0.7-1 mm long in a row over the apex and usually down the outer side, the connective slightly to prominently exceeding the locules at the apex. Ovary 1-1.5 mm high and wide, with all 3 carpels fertile; styles 4-7 mm long. Fruit 2.5-3.5 mm high and wide, contracted at the base.

  • Discussion

    2. Blepharandra hypoleuca (Bentham) Grisebach, Linnaea 22: 7. 1849. Coleostachys hypoleuca Bentham, London Jour. Bot. (Hooker) 7: 125. 1848. Byrsonima cretacea Gleason, Bull. Torr. Bot. Club 58: 378. 1931. Type. Tate 533, Cerro Duida, elev 4800 ft, Amazonas, Venezuela (holotype NY!). Blepharandra cretacea (Gleason) Steyermark, Fieldiana (Bot.) 28(2): 280. 1952. Blepharandra cretacea var composita Steyermark, Fieldiana (Bot.) 28(2): 281. 1952. Type. Steyermark 58191, Cerro Duida, elev 1700-1980 m, Amazonas, Venezuela (holotype F, isotype NY!). Blepharandra ptariana Steyermark, Fieldiana (Bot.) 28(2): 282. 1952. Type. Steyermark 60310, savanna between Santa Teresita de Kavanayen and base of Ptari-tepui, elev 1220 m, Bolivar, Venezuela (holotype F, isotype NY!). Type. Rob. Schomburgk II 677/Rich. Schomburgk 1043, Roraima, Bolivar, Venezuela ["Guiana angl."] (holotype K ; fragment of isotype NY!). Collected in flower and fruit in all months. This exceedingly variable species defies my best efforts to divide it into natural and useful taxa. An extensive series of coHections has been studied, and as often happens with polymorphic species, the more collections one studies the harder it becomes to find groups of correlated characters. It is possible to divide the species on the basis of any of several arbitrarily selected characters, but the membership of the subdivisions keeps changing with the character selected. For this reason I have decided to reject the taxonomy of MacBryde (1970, p 46 et seq) and recognize only B. hypoleuca. Study of MacBryde's key (p 46) wHl illustrate the difficulties. Blepharandra cretacea has the leaves not truly sessile, but with petioles only about 2-3 mm long and obscured by the cordate leaf base. Many collections of otherwise typical B. hypoleuca, from various parts of the range, have the petioles 3-5 mm long. The next character, whether or not the leaf bases are "amplexicaul," is not really a separate character from the first. In plants with cordate leaf bases (a common condition in B. hypoleuca) the base will be more or less "amplexicaul" depending on how short the petiole is. Leaf size is not a good basis for the separation, because small-leaved plants of B. hypoleuca are common. One can, without difficulty, find plants of B. hypoleuca with veins just as prominent as in B. cretacea. Number of hairs on the filament and anther is highly variable, with B. cretacea representing one end of a continuous series; the type of B. cretacea has more than 10 hairs per theca, and many coHections of B. hypoleuca are intermediate between the "many" and "few" condition. Lest it be fell that the combination of these characters will still support B. cretacea, in spite of their individual weakness, I would point to the collections of B. hypoleuca from Auyan-tepui. These collections are Cardona 237 and 2662, Foldats 2602 and 7195, Steyermark 93587 and 93660, and Tate 1174. In general these collections strongly resemble the collections from Cerro Duida that MacBryde calls B. cretacea. Most ofthe Auyan collections have been identified as B. cretacea by Gleason or Steyermark, but according to MacBryde's definition they have to be called B. hypoleuca. This is because he has chosen to place greatest emphasis on the length of the petiole and the number of hairs on the anther (the Auyan material has fewer anther hairs than usual for B. hypoleuca, but more than the Duida specimens). Thus one chooses a character to emphasize and ends up with B. cretacea sensu MacBryde or B. cretacea sensu Gleason and Steyermark. Neither seems to me to warrant recognition. In such a variable species, some discussion of the nature and distribution of the more significant variation is necessary. 1. Leaf base. Every intermediate between truncate to deeply cordate can be found, with much variation even on the same plant. There is little geographical pattern, but the truncate leaf base is perhaps commoner in Guyana and easternmost Venezuela. 2. Leaf and bracteole vesture. With a few exceptions, the leaves on plants from Guyana have few hairs to begin with, and these are soon lost. In most western populations the leaves tend to be and remain more densely hairy. This same general trend holds for bracteoles. 3. Leaf size. Plants with very large and very small leaves have been collected throughout the range of the species, from the Upper Mazaruni River to Cerro Duida. Plants from higher on mountains and in more open vegetation seem often to have smaller, more appressed leaves, but the inconsistency of data on labels makes it hard to assess the significance of this tendency. 4. Inflorescence. Plants with large, many-flowered inflorescences have them "compound," ie each cincinnus consists of several flowers. Plants with tighter, fewer-flowered inflorescences have a reduction in the number of flowers per cincinnus, culminating in the pseudoraceme of some plants from Cerro Duida. 5. Stamen hairs. Most collections have many long, stiff, basifixed hairs on the filament and anther, especially at the apex of the anther. However, plants with relatively few shorter hairs on the anther have been collected on Auyan-tepui, on the Chimanta Massif, and on Cerro Duida. In addition to these characters, other interesting but apparently trivial variations occur. The sepals are nearly eglandular in Foldats 2602, and that plant also has the connective of the anther extended well beyond the locules, which condition occurs sporadically elsewhere to varying degrees. The stipules are more belatedly deciduous in plants from Cerro Duida than is usual. Steyermark & Wurdack 1052, from Torono-tepui, is notable for the size of its petals and their red claws, and the density and dark color of the tomentum in the inflorescence. The variation in this species seems best interpreted as a combination of geographical clines, such as are found in many species and can be identified in herbarium material, and probably ecological variation and differentiation. The latter needs to be studied in the field, where careful analysis of the habitats and associated vegetation may yield an understanding of some of the diversity.

  • Distribution

    Distribution. Eastern Guyana, Bolivar, Venezuela, and Cerro Duida. GUYANA. Chinpweng, Wandabu Mountain, Forest Dept. 7842 (NY); Krabu Savanna, on rocks in open. Forest Dept. 7980 (NY); upper Mazaruni River, Imbaimadai Savannas, in shallow sand on sandstone, elev 550 m, Maguire 32191 (K, MICH, NY); Pakaraima Mts, Kamarang River-Wenamu TraH, Samwarakna-Tipu, elev 1100 m, Maguire & Fanshawe 32485 (K, MICH, NY, US), elev 3350 ft, Maguire & Fanshawe 32561 (K, NY); Kamarang River Crossing, Kamarang He

    Venezuela South America| Guyana South America|