Theobroma glaucum H.Karst.
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Authority
Cuatrecasas, José. 1964. Cacao and its allies, a taxonomic revision of the genus Theobroma. Contr. U. S. Natl. Herb. 35: 379-614. pl. 1-12.
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Family
Malvaceae
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Scientific Name
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Type
Types: Karsten s.n. Colombia, San Martín. Schultze-Rhonhof 2312, Ecuador, Papayacu (of T. calodesmis, formerly in Berlin).
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Description
Description - Tree 8-15 m. high; stem up to 30 cm. in diameter, with grayish, inside reddish bark and white wood; sympodial growth by lateral, subterminal, upright shoots; primary branches ternate, regularly dichotomous, spreading, deciduous when old, the terminal minutely stellate-pulverulent with additional simple, spreading hairs, soon glabrate, smooth, rather shining, dark brown or somewhat purplish; stipules linear-subulate, 4-5 mm. long, sparsely stellate-pilose, soon deciduous. Leaves coriaceous, rather rigid, distichous; petiole robust, densely ferruginous or brownish tomentose with stellate hairs, transversely rimose when dry, 0.8-1.8 cm. long; blades oblong-ovate or ovateoblong, broad in the lower third, obtusely cuneate at base, narrowed near the apex, prolonged with a long slender appendage, the margin entire or slightly sinuate and slightly revolute, 16-36 cm. long, 7-13 cm. broad, the acumen 2-3.5 mm. long, shining above, green, pale olivaceous brown when dry, apparently glabrous but with sparse mediocre stellate hairs and callose scar-dots on the nerves, the costa and secondary nerves prominently filiform, the others slender, more or less noticeable, somewhat cinereous beneath, glaucous or pale rosy, with a glabrous aspect but the rather shining, pale brownish principal nerves sparsely callose-dotted and with very scarce ferruginous, stellate hairs, the small veins glabrous, the areoles covered with a very appressed microscopic tomentum of minute, white, stellate hairs, the costa very prominent, the 4 or 5 pairs of secondary nerves prominent, the basal one at an acute angle (remote from the margin), ascending, the others curved-ascending, near the margin becoming slender, decurrent, curving, anastomosing, the cross-tertiary nerves thinner, prominent, 3-10 mm. distant from each other, the lesser veins minutely prominulous-reticulate; leaves of the ortho tropic spreading-puberulous branches long-petiolate, with the blades attenuate-cuneate at base, the lower pair of nerves very close to the margin, the petiole slender, 3.5-4 cm. long. Inflorescences on the trunk, often many-flowered and showy, with up to 200 flowers, the base woody-tuberculate; branches 3-many, mediocre, 4-6 cm. long, furcate-ramose from near the base, the branchlets fastigiate, angulate, rather rigid, ferruginous-tomentose, the terminal (peduncles) moderately robust, 3-4 mm. long, articulate to pedicel, this 5-15 mm. long, striolate, slightly thicker, tomentellous, the subtending bracteoles minute, ovate-lanceolate, about 1 mm. long, very soon deciduous; buds ovoid, round at base, subacute at top, densely stellate-tomentose, 8-9 mm. long, about 6 mm. broad. Calyx umbilicate; sepals thick, lanceolate-oblong, acute, inflexed at apex, connate for 2 mm. at base, densely and appressed stellate-tomentose outside, within minutely, whitish stellate-pilose near the margin and glandular at base, otherwise subglabrous, 12-13 mm. long, 3.5-4 mm. broad, curved-spreading after anthesis. Petal-hoods light red, oblong-obovate, shortly unguiculate at base, rounded cucullate at apex, the end emarginate, biauriculate, articulate to the lamina, the 3-nerves prominent inside, thin, with spreading, weak, sparse hairs outside, 5-6 mm. long, 2.5-3 mm. broad; petallamina red crimson, thick, minutely rugose, and more or less translucid-venulose, glabrous, suborbicular or broadly elliptic, subsessile at base, abruptly contracted into a short claw, minutely sinuate at margin, 5.5-7 mm. long, 5-6.5 mm. broad, the claw 0.5 mm. long. Staminal tube about 2 mm. high and 2.5 mm. in diameter; staminodes red crimson, erect, lanceolate-subulate, acute at apex, fleshy, minutely muricate-pilose, 10-12 mm. long, 1.4-1.8 mm. wide above base; filaments flexuose, 2.5-3 mm. long, glabrous, shortly 2 or 3 furcate at apex, bearing 2 or 3 anthers, the loculi ellipsoid, convergent, 0.5-0.6 mm. long; ovary oblong, about 2 mm. long, 5-ridged and sulcate, hirsute-tomentose; styles connivent, 3 mm. long, united only at base. Fruits ellipsoid-oblong, obtusely pentagonal, broad and umbilicate at base, more or less attenuate and subacute at apex, the pericarp 1 cm. thick, coriaceous, rigid, densely and minutely velutinoustomentose, bluish greenish, 11-13 cm. long, 5.5-9 cm. broad; seeds 2-2.3 x 1.2-1.4 x 0.9 cm.; fruiting peduncle robust, 7-8 cm. long, 1-1.5 cm. thick; germination epigeous.
Uses - According to Karsten, the seeds are used as cacao by the natives, being very similar to the true cacao. Schultze-Rhonhof gives the indigenous name "chucú" for the fruit which, according to her, is very much appreciated by the natives.
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Discussion
According to Baker and his associates the cotyledons are white and the pulp is pale orange and of a very sweet taste. The type collection of T. calodesmis was destroyed during the war in Berlin; it was collected by Hertha Schultze-Rhonhof near Papayacu at about 200 m. altitude on the Bonanza River, a tributary of the Pastaza River in eastern Ecuador. The description given by Diels makes it possible to identify his species perfectly with several Amazonian collections from nearby regions of Colombia, Peru, and Brazil. The sterile type specimen of Theobroma glaucum, collected on the Llanos de San Martín, agrees perfectly with a specimen that is almost a topotype, collected by Philipson, Idrobo, and Fernández in the foothills of the Sierra Macarena, Intendencia del Meta. I have no doubt that all these collections represent the same species, which extends from the upper Orinocia to upper Amazon basin on both sides of the great river. Diels did not see fruits but gave an accurate description of the foliage and flowers; he related his species to T. speciosum on account of the texture and tomentum of the leaves, and also to T. bernouilllii, but he says that the leaves are broader, the inflorescences larger, the flowers larger, and the staminodes longer.
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Common Names
cacao de monte, cacao silvestre, chucú, bicco