Zygia longifolia (Humb. & Bonpl. ex Willd.) Britton & Rose

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

Zygia longifolia (Humb. & Bonpl. ex Willd.) Britton & Rose

Type

"Habitat in America meridionals — Holotypus, a single lf, collected (Humboldt, Bonpland & Kunth, 1823: 298) "prope Cavico Bracamorensium, ad ripam fluminis Chamayae, alt. 350 hex. [near 6°S, 79°W in S Jaén, Cajamarca, Peru, at ±635 m]." — Holotypus, annot

Synonyms

Inga longifolia R.S.Cowan, Feuilleea longifolia (Willd. ex Humb. & Bonpl.) Kuntze, Mimosa ligustrina Vahl, Inga falciformis DC., Pithecellobium longifolium (Humb. & Bonpl. ex Willd.) Standl.

Description

Species Description - Macrophyllidious cauliflorous trees 6-20(-24) m with trunk attaining 1 m dbh (mostly less), sometimes flowering as arborescent shrubs 2.5 m upward, appearing glabrous and the mature foliage always so, the axes of the inflorescence commonly puberulent, the dull olivaceous lfts bicolored, pale beneath, the fragrant white, either white- or pink-stamened fls borne in short simple spikes fasciculate on knots along annotinous and older branches. Stipules depressed-deltate, deltate, ovate or lanceolate, obtuse or acute, 0.8-2.6(-3) mm, nerveless or faintly 1-3-nerved dorsally, deciduous. Lf-formula 1/1½(-2½), all but very occasional depauperate lvs exactly 6-foliolate, the distal pair of lfts about twice as long as the proximal one, this inserted at or usually much below middle of pinna-rachis; lf-stks 2-13(-20, commonly <10) x 0.8 2 mm, shallowly sulcate ventrally; a round, buttonshaped or shallowly cupular nectary 0.7-2.2 mm diam at tip of lf-stk and a scarcely smaller one at tip of each pinna-rachis; rachis of pinnae (0.7-) 1.3-4.5 cm; pulvinule of distal lfts 1.2-3 mm; blade of lfts either broadly or narrowly elliptic, elliptic-oblanceolate, or ovate-elliptic, from inequilaterally cuneate base, acute or shortly acuminate, the distal pair (7—)9— 16 x (1.5-) 2.2-5(-6.5) cm, (2.3-)2.7-4.8 times as long as wide; venation of lfts pinnate, the subcentric, straight or almost straight midrib giving rise on each side to 6-10 major (and often random intercalary) secondary nerves, these slenderly prominulous on both faces or only beneath, the tertiary and reticular venulation faint or fully immersed. Fl-spikes (10—) 12—30-fld, the axis including short peduncle (5-)8-23(-30) mm; bracts ovate acute 0.6-0.9 mm, persistent; perianth glabrous or puberulent, especially toward orifice of calyx and corolla, the calyx faintly 5(-10)-nerved, the greenish white or pinkish corolla-tube striately nerved, the erect ovate lobes nerveless; calyx shallowly or deeply campanulate 0.7-2.4 x 0.8-1.3 mm, the teeth 0.15-0.5 mm, the tube often ruptured by expansion of the nectarial disc; corolla (4.5-)5-7(-8.2) mm, the often unequal lobes 0.5-1.4 mm; androecium 20-30(re- doubled, to 54)-merous, 14.5-21 mm, the whitish tube (6.5-)7-10.5 mm, exserted 1-4.5(-5) mm, variably dilated upward, the tassel white or pink; nectarial disc 0.3-0.6 mm tall; ovary linear, glabrous; stigma poriform, ±0.1-0.2 mm diam. Pods l(-2) per spike, pendulous, sessile or almost so, broad-linear, planocompressed becoming at maturity low-convex over seeds, highly variable in length, width and curvature, nearly straight to strongly falcate and when proportionately long also randomly twisted, in profile (6-)8-44 x 1.4-2.2 cm and when well fertilized 10- 17-seeded, the prominulous sutures either nearly straight or undulately constricted between seeds, the coriaceous valves dark brown when ripe, weakly venulose, glabrous; seeds ordinarily subvertically descending, in broad view oblong-elliptic 17-29 x 9-13 mm, in some shorter pods (see discussion) horizontal and only 8-13 x 6-10 mm, the papery brown testa finely wrinkled, dull, lacking pleurogram.

Distribution and Ecology - Riverbanks, gallery woodland, streambed thickets, seasonally flooded mixed forest or palm forest, ascending from the edge of mangrove near sea level into premontane wet forest, in Costa Rica to 600-1250 m, in Colombia to 800-900 m, in Peru to 1150-1500 m, widespread and locally abundant in Central and Andean South America between ±15°N and 10°S: NE Honduras S and E to N Colombia and NW Venezuela, thence S along the Pacific slope to Piura and Cajamarca and through intermontane valleys and E foothills of the Andes to Junín. — Map 33. — Fl. intermittently through the year, but most profusely VI-I.

Discussion

Some Peruvian specimens, from depts. Piura (Angulo 4114, NY), Huánuco (Swingle 29A, NY), and Amazonas (.Berlin 851, NY) are distinguished by short broad pods ±6-13 x 1.7-1.9 cm in which the relatively short seeds are oriented across (not parallel to) the fruit’s long axis. There is no apparent difference in foliage from other Andean material with the long fruit and descending seeds of what is ordinarily accepted as genuine Z. longifolia. More observations of flowering and correlated fruiting material are needed, and it must be borne in mind that Humboldt’s Inga longifolia, collected in flower, could very well turn out to have fruits of the modified shortened type.

Common Names

guaná, sotocaballo, azote-caballo, apa , Amé, chiparo , chipero, guamo prieto, pichindé, buscilla , bushica, chichimbina, Samik

Distribution

Piura Peru South America| Cajamarca Peru South America| Junín Peru South America| Costa Rica South America| Colombia South America| Honduras Central America| Venezuela South America|