Swartzia macrocarpa Spruce ex Benth.

Authority

Cowan, Richard S. 1967. Swartzia (Leguminosae, Caesalpinioideae Swartzieae). Fl. Neotrop. Monogr. 1: 3-228. (Published by NYBG Press)

Family

Fabaceae

Scientific Name

Swartzia macrocarpa Spruce ex Benth.

Type

Type collection. R. Spruce 1404 (lectotype K; isolectotypes BM, CGE, Fl, G, M, NY), Barra (Manáos), Amazonas, Brazil, Feb. 1851. Bentham in his original description cited two Spruce collections; this one is chosen rather than Spruce 1330 because the latter is less widely distributed and the collection selected seems to represent the species a little better. Many of the isolectotypes are not numbered 1404 but the collection data make it certain that these are identical with the sheet at Kew; each of the cited sheets, including the Kew sheet, bears the manuscript name S. stipularis, in Bentham's hand, but this was not validly published.

Synonyms

Tounatea macrocarpa (Spruce ex Benth.) Taub., Tunatea macrocarpa (Spruce ex Benth.) Kuntze

Description

Description - Tree to 5 m tall, the branchlets sparsely strigulose but early glabrescent; stipules foliaceous, deciduous, (3-)lG-20(-25) mm long, (2-)4-7 mm wide, falcate, elliptic to lanceolate or ovate, acuminate or acute, minutely strigulose sparingly on the outer surface, glabrous within, reticulate-venose; petioles canaliculate on the upper surface, stipellate apically, (2.5-)4-6 cm long, glabrous or sparingly strigulose and glabrescent; rachis glabrous or glabrescent, (7.5-)8.5-12 cm long, the upper surface flat or canaliculate, sometimes marginate, stipellate at each pair of leaflets; leaflets (2-) 3-jugate, the petiolules 2-3 mm long, glabrous or glabrescent, the blade elliptic, 9-21 (-26) cm long, 3-6(-8) cm wide, the base acute or narrowed but finally obtuse, the apex acute to acuminate, often mucronulate, glabrous or the veins minutely strigulose to varying degrees and glabrescent, the veins slightly salient on the upper surface, salient beneath; inflorescence (9.5-) 11 -23(-28) cm long, racemose or panicled-racemose, ramigerous or cauligerous, the axis minutely strigulose, the bracts deciduous to persistent, (1.5-)2-3.5 mm long, 1-2 mm wide, obtusely to acutely triangular or broadly ovate, minutely strigulose externally, glabrous within, the bracteoles usually not developed, rarely vestigial at the pedicel-apex; pedicels (10-) 15-18 mm long, minutely strigulose; buds subglobose to oval in outline, umbonate, 9-12 mm long, 7-8 mm diameter, minutely strigulose; calyx segments 3-4, deciduous, glabrous within, minutely strigulose on the outer surface; petal yellow, glabrous, the claw 3 mm long, the blade rounded, ca 15 mm diameter or oblate and 22-25 mm long, 26-30 mm wide; larger stamens 6, glabrous, the filaments 18 mm long, the anthers narrowly oblong, ca 5 mm long and 1-1.5 mm wide, the smaller stamens glabrous, the filaments 8-13.5 mm long, the anthers oblong, the apex subacute, 1.5 mm long, 0.5-0.7 mm wide; stigma capitellate; style 3.5-5 mm long, sparingly strigulose; ovary arcuate-linear, ca 7-13.5 mm long and 1-1.5 mm wide, sparsely strigulose, the gynophore 7-12 mm long; mature fruit not seen, immature ones narrowly moniliform.

Discussion

Swartzia macrocarpa has a certain superficial resemblance to S. laurifolia and there is no closer relationship discernible at this point. Like S. fraterna, to which the present species is also related, S. macrocarpa has an almost glabrous gynoecium in contrast to the densely sericeous one of S. laurifolia. Swartzia macrocarpa differs from both its near relatives in form and number of pairs of leaflets and presence or absence of pubescence on the gynoecium.

Distribution

(Fig. 8). Seasonally or more or less permanently inundated lands along rivers and smaller streams, principally along the lower reaches of the Rio Negro in northwest Amazonas, Brazil; also along tributaries to the Amazon River just below Manáos.

Brazil South America| Amazonas Brazil South America|