Pithecellobium dulce (Roxb.) Benth.

  • Authors

    Rupert C. Barneby

  • Authority

    Barneby, Rupert C. & Grimes, James W. 1997. Silk tree, guanacaste, monkey's earring: A generic system for the synandrous Mimosaceae of the Americas. Part II. , , and . Mem. New York Bot. Gard. 74: 1-149.

  • Family

    Mimosaceae

  • Scientific Name

    Pithecellobium dulce (Roxb.) Benth.

  • Type

    Holotypus (Nielsen, 1979: 34): Roxburgh s.n., K (hb. Bentham, via Forsyth) e Coromandel!. — Inga dulcis (Roxburgh) Willdenow, Sp. Pl. 4: 1005. 1806. — Feuilleea dulcis (Roxburgh) O. Kuntze, Revis. Gen. Pl. 184. 1891. — Zygia dulcis (Roxburgh) Lyons, Pl. N

  • Synonyms

    Inga pungens Willd. ex Humb. & Bonpl., Mimosa monilifera Bertol., Acacia obliquifolia M.Martens & Galeotti, Inga leucantha C.Presl

  • Description

    Species Description - Trees potentially attaining 15-18 m, with one or several trunks to ±3 dm dbh, when well grown with rounded crown and pliantly pendulous branchlets but fertile as a bushy treelet and in less favorable habitats maturing at 2-3 m; stems randomly armed at nodes of long-shoots with pairs of stout ascending straight stipular spines but the stipules toward the inflorescence and those of axillary brachyblasts stiffly subulate and much shorter, the annotinous and older branches densely pallid-lenticellate, the homotinous ones together with lf-axes densely pilosulous to glabrous but the inflorescence always more or less pilosulous with ascending or erect whitish hairs to 0.1-0.45 mm, the foliage olivaceous, moderately bicolored, the lvs of long-shoots relatively ample but diminished upward or reduced to a rudimentary petiole, the lfts either glabrous, or glabrous except for a tuft of hairs dorsally in posterior angle of midrib, or thinly to minutely strigulose beneath only or on both faces, the small dense subspherical capitula of whitish, greenish-ochroleucous or rarely pink-tinged fls borne, mostly fasciculate by 2-4 but some solitary, in either axillary or terminally paniculate pseudoracemes, these often appearing efoliate but each fascicle of peduncles usually subtended by a rudimentary lf-stk charged with a nectary. Stipular spines potentially attaining 13 mm, but commonly much shorter, and stipules of many young branches subulate, scarcely indurate and <2 mm, many herbarium spms unarmed. Lf-formula i/1, each lf 4-foliate; lf-stk of lvs below the inflorescence 6-45(-55) mm, a little dilated distally and near apex (0.5-)0.6-l mm diam; a subsessile or stoutly short-stipitate, thick-rimmed nectary 0.3-0.7(-0.8) mm tall and 0.4-0.7 mm diam at tip of each lf-stk and a similar one at tip of each pinna-rachis; lfts obliquely elliptic, oblong-elliptic, or the largest obovate- or ovate-elliptic, from inequilateral, cuneate to shallowly semicordate base, either obtuse, or obtuse mucronulate, or emarginate, the larger ones 23-56 x 9-32 mm, (1.5—)1.6—2.8(-3) times as long as wide; venation pinnate, the gently porrect, only slightly excentric midrib giving rise on each side to 4-7(-8) major (and random intercalary) secondary nerves, brochidodrome well within the plane margin, and these in turn to an irregular open mesh of tertiary venules, the whole venation usually low-prominulous on both faces. Longer peduncles 4— 20(-24) x (0.35-)0.4-0.6 mm; capitula (15-) 18-29- fld, the subspherical or shortly clavate receptacle 1-2.5 mm; fls either all bisexual or often many (all) of a capitulum functionally staminate, all 5-merous or few random ones 6-merous, all homomorphic, the perianth finely densely gray-silky-puberulent overall; bracts oblong or spatulate 0.6-1.3(-l.6) mm, persistent; calyx campanulate or turbinate-campanulate (l.l-)1.3-2(-2.2) x 1-1.8 mm, the usually depressed- deltate, sometimes triangular teeth 0.1-0.4(-0.6) mm; corolla (2.5-)2.8-4.3(-4.6) mm, the erect ovate lobes 0.7-1.6 x 0.7-1.1 mm; androecium (22-)26-42-merous, 7-10.5(-11.5) mm, the stemonozone 0.350.5 mm, the tube (l-)1.4-3.2 (-3.5) mm, sometimes a trifle callous internally at base but lacking a true disc; ovary stipitate, the stipe glabrous, that of bisexual fls (0.5-)0.8-1.8 mm, the linear-ellipsoid, densely minutely pilosulous or sometimes more thinly pilosulous body (1-)1.2-2.1 mm; style of fertile fls shortly exserted, scarcely dilated at the stigma. Pods usually solitary, sometimes 2-3 per capitulum, undulately linear and loosely decurved through ±1-2 circles to form an open ring or equivalently contorted, the body when well fertilized 8-12-seeded, shallowly or (where ovules abort) deeply constricted between seeds, measured along middle of valves 9-17.5 cm long and at each seed (7.5—)8—17(—21) mm diam, at maturity a little compressed but plumply biconvex at each seed, the reddish brown, green and red-cheeked, or bright rose-red, internally red-brown, thinly fleshy valves becoming stiffly papery and coarsely venulose, either thinly or densely pilosulous when young but often glabrate at early maturity; dehiscence through both sutures, the valves both recurving and coiling; seeds persistent after dehiscence, nidulated by the scalloped, white or reddish pink aril, plumply compressed-lentiform 7-13 x 6-11 x 2-4 mm, the hard black, lustrous but often minutely rugulose or punctate testa 0.15-0.25 mm in section, closely investing the homy pallid embryo; germination crypto-cotylar, the first 2 eophylls simply pinnate, bifoliolate, the third and subsequent lvs bipinnate 4-foliolate. Pithecellobium dulce is distinguished among species with 4-foliolate leaves and truly capitate flowers (receptacle at most 2.5 mm) by puberulent- pilosulous, stipitate ovary.

    Distribution and Ecology - Evergreen or almost so, the lf-fall and lf-flush often overlapping; native in seasonally dry, brush or woodland communities in lowland E and W Mexico (S from Baja California Sur, S Sonora, and Tamaulipas), Central America, inter-Andean Colombia, and W Venezuela, from sea level to ±1550 m, but dispersed in early Spanish colonial times to West Indies, the Philippines, and tropical Asia, where extensively naturalized, and later planted and escaping to waste lots in subtropical Florida, Hawaiian Is., Guyana, E Brazil, and elsewhere, a common ornamental and shade tree in Latin America, where also grown for the edible seed-aril. — Map 8. — Fl. abundantly following rains, intermittently, as moisture permits, throughout the year.

  • Discussion

    The typical form is characterized by relatively short peduncles (to 4-12 mm) and wide pod (10-16, seldom -21 mm at the seeds), and is apparently native to Pacific Mexico, introduced in Asia, the West Indies, Florida, and elsewhere. In southern Mexico, Central America, and northwest South America the longer peduncle of each fascicle is commonly between 1 and 2 cm long and the pod is narrower, about 8-12 mm wide at the seeds. These variations are not well correlated, and we have no certainty as to the native status of many collections. Independently of these characters the foliage varies from glabrous to pubescent on one or both faces of the leaflets, with or without a dorsal tuft in the posterior angle of the midrib. No differential character was given in the protologue of P. littorale, which has long been syn- onymized with P. dulce. Pittier tentatively distinguished P. microchlamys by supposed differences in leaflet pubescence and small flower size, but these are ineffective in practice.

    An anomalous flowering specimen from the upper Magdalena valley in Tolima, Colombia (Sandeman 5700, K) has foliage and individual flowers of P. dulce, but the flowers are borne in oblong spikes (receptacle ±9-11 mm) rather than in capitula. Sand with in annotation suggested that this might represent an undescribed species, but it is as plausibly interpreted as a taxonomically insignificant variant of P. dulce, which is known from the same region in typical form.

    for further vernacular names in the Americas see Safford, Contr. U.S. Natl. Herb. 9: 356. 1905; Standley, 1922: 393; and in the Old World: Zingg, Philippine J. Sci. 54: 250-252 (many local corruptions of guamúchil). 1934; Kostermans, 1954: 8. — Furnishes honey, gum, tanbark, used in folk medicine, and the aril eaten raw or in infusion.

  • Common Names

    Guamúchil, huamúchil, pinsón , guamo bianco, yacure, azabuche, dinde, ojito de Nena, payandé clavo , gallinero, ingá dulce, guamá americano, acacia à bracelets, diabelle, bread and cheese

  • Distribution

    Baja California Sur Mexico North America| Sonora Mexico North America| Tamaulipas Mexico North America| Colombia South America| Venezuela South America| Philippines Asia| West Indies| Guyana South America| Florida United States of America North America| Hawaii United States of America North America| Brazil South America|