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Flora of the Venezuelan Guayana

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16. UNONOPSIS R.E. Fr., Kongl. Svenska Vetenskapsakad. Handl. n.s. 34(5): 26, t. 4, figs. 3--8. 1900.

by Paul E. Berry

Shrubs or small to medium-sized trees with simple hairs. Inflorescences often branched, ramiflorous or cauliflorous, axillary; pedicels articulate above the basal bract and provided with a second bract above the articulation. Flowers small, bisexual; flower buds globose, ovoid, or conical; receptacle truncate at the apex. Sepals mostly small, valvate; petals 6, 2-seriate, rigid, valvate, ovate or suborbicular, concave, the interior ones thickened. Stamens 10--200; anther locules not locellate; connective dilated above the anther into a truncate disk. Carpels 10--ca. 60; ovule solitary and almost basal or up to 6--8 and lateral. Monocarps free, stipitate or nearly sessile, 1--6-seeded. Seeds pitted, without an aril.

Central America, Lesser Antilles, Colombia, Venezuela, Guyana, Suriname, French Guiana, Ecuador, Peru, Brazil, Bolivia; ca. 40 species, 5 in Venezuela, all of these in the flora area.

Unonopsis angustifolia (Benth.) R.E. Fr. is known from neighboring Brazil along the Rio Uaupes and may be expected in the flora area. It has leaves 4--5 times longer than broad and an acumen 3--4 cm long.

Key to the Species of Unonopsis

1. Rachis of the inflorescence 7--15 cm long, subpaniculately branched with 6 or more branches, many-flowered...U. glaucopetala

1. Rachis of the inflorescence < 7 cm long, with 3 or fewer branches, or else unbranched, few- to several-flowered...2

2(1). Young stems, inflorescence rachis, and young fruits densely velutinous; sepals 6--7 mm long and wide; monocarps large, globose, 20--25 mm diameter, subsessile, the stipes 1--3 mm long...U. velutina

2. Young stems, inflorescence rachis, and young fruits glabrous to pubescent; sepals 1.5--3 mm long and wide; monocarps oblong- or clavate-ellipsoid to globose, if globose then smaller than above, the stipes 5--24 mm long...3

3(2). Stipes of the monocarps 17--35 mm long; monocarps often numerous (15--60 per receptacle or else numerous scars visible), ellipsoid; seed solitary and basal; leaves narrowly obovate and shortly acuminate...U. stipitata

3. Stipes of the monocarps shorter, 5--12 mm long; monocarps generally fewer (mostly < 15 per receptacle), oblong-ellipsoid or globose, not acutely contracted at the base; seeds several per monocarp and lateral or else solitary and pendulous...4

4(3). Monocarps 20--26 mm long; seeds 10--15 mm diameter; bracts borne at the base of the pedicel...U. grandis

4. Monocarps generally < 20 mm long; seeds 8--10 mm diameter; bracts borne on the lower 1/3 of the pedicel...U. guatterioides

Unonopsis glaucopetala R.E. Fr., Bull. Herb. Boissier sér. 2, 7: 1004. 1907. ---Yarayara, Yarayara negra.

Tree 10--20 m; leaves insculpted or minutely verruculose on glabrous lower surface, midvein and veins sparsely pubescent; flowers pale green; monocarps globose, glabrous; fruits turning dull red. Semideciduous, riparian, and evergreen lowland forests, ca. 50--300 m; Delta Amacuro (Río Amacuro, Río Cuyubini, Serranía de Imataca), Bolívar (Altiplanicie de Nuria), Amazonas (Río Cuao, Río Orinoco). Guyana, Suriname. Fig. 388.

The bark boiled in water is used locally as a remedy for snake bites and for the bite of Paraponera clavata ants.

Unonopsis grandis (Benth.) R.E. Fr., Kongl. Svenska Vetenskapsakad. Handl. n.s. 34(5): 28. 1900. ---Trigynaea grandis Benth., J. Proc. Linn. Soc., Bot. 5: 70. 1860.

Shrub or small tree to 6 m; seeds several per monocarp. Riparian forests, 100--200 m; Amazonas (Río Casiquiare, Río Cuao, Río Negro, Salto Huá on Canal Maturacá). Peru, Brazil (Amazonas).

Unonopsis guatterioides (A. DC.) R.E. Fr., Acta Horti Berg. 12: 241. 1937. ---Uvaria guatterioides A. DC., Mém. Soc. Phys. Genève 5: 202. 1832.

Shrub or tree to 10 m. Lower montane evergreen forests, ca. 500 m; Bolívar (Cerro Ich&;n). Guyana, Suriname, French Guiana, Amazonian Peru and Brazil. Fig. 387.

Unonopsis stipitata Diels, Verh. Bot. Vereins Prov. Brandenburg 47: 130. 1905. ---Majagua, Majagua candelero, Majagua negra.

Slender tree 4--12 m; leaves mainly glabrous throughout or sometimes with the midrib pubescent; flowers creamy to yellowish white; fruits orange. Evergreen lowland forests and semideciduous forests near savanna openings, often on lateritic soils, borders of igneous outcrops, ca. 100--300 m; Amazonas (Coromoto, Río Mawarinuma, Río Siapa, near San Carlos de Río Negro). Guyana, Suriname, French Guiana, Amazonian Peru and Brazil.

Unonopsis velutina Maas, Proc. Kon. Ned. Akad. Wetensch. C 89: 275, figs. 11e & 19. 1986. ---Tanoajua (Piaroa).

Tree 6--10 m; young twigs and lower surface of leaves densely velutinous; leaves 16--27 × 5.5--10 cm; flowers cream-colored; monocarps densely yellow-brown pubescent at first, eventually glabrescent, stipes very short. Semideciduous and evergreen lowland forests bordering igneous outcrops, moist forests on diabase, 100--400 m; Bolívar (upper Río Caura), Amazonas (Coromoto, Río Cataniapo). Endemic.


Scientific Comments:
Paul Berry (peberry@facstaff.wisc.edu) or Kay Yatskievych (kay.yatskievych@mobot.org).

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