Swartzia leptopetala 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 leptopetala Benth.

  • Type

    Type collection. L. Riedel 34 (holotype K; isotype LE), near Obidos, Amazonas, Brazil, Oct. 1828. Another sheet at the Harvard Herbaria, collected by Riedel but without a collection number, is perhaps an isotype.

  • Synonyms

    Swartzia discolor Poepp. & Endl., Swartzia fugax Spruce ex Benth., Tounatea fugax (Spruce ex Benth.) Britton, Tounatea discolor (Poepp. & Endl.) Taub., Tunatea discolor (Poepp. & Endl.) Kuntze, Tunatea fugax (Spruce ex Benth.) Kuntze, Tounatea leptopetala (Benth.) Taub., Tunatea leptopetala (Benth.) Kuntze, Swartzia melanoxylon Ducke, Swartzia rotundata R.S.Cowan

  • Description

    Description - Tree 8-30 m tall, the trunk 0.4-1 m diameter, the branchlets microscopically malpighio-strigulose; stipules caducous to persistent, triangular or occasionally arcuate-oblong, acute, 0.5-1 (-3) mm long, microscopically malpighio-strigulose externally, glabrous within; petioles terete, usually stipellate apically, (1.5-)3-5 (-7.5) cm long, densely malpighio-strigulose microscopically, sometimes glabrescent; rachis (2.5-)6.5-12.5(-18.5) cm long, terete or marginate or shortly alate or usually at least stipellate at each pair of leaflets, microscopically malpighio-strigulose; leaflets (2-)3- or 4-(-5) jugate, the petiolules (1-)2.5-4(-5) mm long, microscopically malpighio-strigulose, the blades oval, elliptic, or oblong-elliptic, the apex bluntly acute to rounded-obtuse, the base obtuse, subobtuse, or acute, those of the lowermost pair smallest, 4-9 cm long, 2-4.5 cm wide, those of the other pairs 6-15.5(-25) cm long, 2.5-6.5(-10) cm wide, all the blades discolorous on the two surfaces, glabrous and nitid on the upper surface or puberulous on the costa, sparingly malpighio-strigulose microscopically and sometimes glaucous beneath, sometimes glabrescent, the venation usually obscure on the upper surface and the costa slightly impressed and the primary veins plane, both the costa and the primaries salient beneath; inflorescence racemose or panicled-racemose, borne in ramigerous to cauligerous fascicles, (4-)7.5-18.5(-26) cm long, the axis microscopically malpighio-strigulose densely, the bracts persistent or occasionally deciduous, triangular, 0.5-0.8(-l .5) mm long and wide, acute, pubescent like the axis externally, glabrous within, the bracteoles lacking; pedicels (4-)7-10(-17) mm long, microscopically malpighio-strigulose densely; buds mostly globose, rarely elliptic, ca 4-6 mm diameter; calyx segments 3 or 4, persistent, microscopically malpighio-strigulose externally, glabrous within; petal yellow, glabrous, the claw 1-5 mm long, the blade obovate to oblate-obovate, truncate to cuneate basally, 5-8 mm long, 4-12 mm wide; larger stamens 2-4, caducous, the filaments 5-9 mm long, glabrous or sparingly strigose, the anthers 2-3.5 mm long, 0.5-1 mm wide, oblong to narrowly oblong, the smaller stamens glabrous, the filaments 4-9 mm long, the anthers oblong to oval, 1-1.5 mm long, 0.5-0.7 mm wide, the pollen from all stamens almost globose and 26 µ diameter; gynoecium sericeous, the hairs malpighiaceous, the stigma truncate to capitellate, the style 0.5-1.5 mm long, the ovary 4.5-6.5 mm long, 1-2 mm wide, arcuate, elliptic to narrowly oblong, the gynophore 3-4.5 mm long, sometimes partly glabrous; fruit elliptic to oblong in outline, 4.5-9.5 cm long, 2-2.5 cm wide, densely strigulose minutely, the stipe 1.5-2.5 cm long.

  • Discussion

    Several collections made by Ducke were listed by him when he described S. melanoxylon but he did not designate a type; I have not selected a lectotype, since the name is here treated as a synonym.

    The relatively large number of synonyms for this species is indicative of its wide range and its morphologic diversity. Actually, however, the diversity is mostly superficial, being largely concerned with differences in the form of the leaflets. Ducke’s synonym S. melanoxylon resulted largely from lack of comparative material and his assumption that, since S. fugax, to which he related his species, was known only from the riverine forest, his species was distinctive in its habitat-high land along the river and sandy savannas. However, there are no good morphological differences. When I described S. rotundata, a half dozen differences were listed to separate it from S. fugax, which I knew only from the description and a photograph. It appears now that none of these is of any value.

    Poeppig & Endlicher related their S. discolor to the earlier S. leptopetala but did not indicate what differences separated them, probably because of their lack of knowledge regarding the latter; Bentham’s type collection is still represented only at Kew and Leningrad. The slight differences in aspect of the leaflets in the original material of S. fugax apparently induced Bentham to describe a new species, but the differences are certainly not specific.

    There is considerable morphological similarity between this species and S. corrugata and S. laurifolia. The .evenose, or nearly evenose, appearance of the upper surface of the leaflets in S. leptopetala is a characteristic shared with S. laurifolia but the latter has relatively large stipules, about twice or more as long as the largest found in S. leptopetala. In addition, S. leptopetala has smaller buds and pedicels, shorter stamens, and the upper and lower surfaces of the leaflets are usually markedly discolorous. Swartzia corrugata, although closely related in floral structure, differs quite clearly in its rugose and rugulose leaflets.

  • Common Names

    Arapary da terra firme, carrasposo, congrio, cumbeira, jacaranda, jacaranda do campo coberto, muirapixuna, mututy, pao preto, Tachy’rana

  • Distribution

    (Fig. 8). Riverine forest, seasonally inundated or not, and in sandy savannas in the Amazon Basin in Brazil and Colombia, 80-300 m alt.; also frequent in southern Venezuela at similar elevations.

    Colombia South America| Vaupés Colombia South America| Amazonas Colombia South America| Vaupés Colombia South America| Delta Amacuro Venezuela South America| Guárico Venezuela South America| Venezuela South America| Apure Venezuela South America| Bolívar Venezuela South America| Amazonas Venezuela South America| Brazil South America| Amazonas Brazil South America| Pará Brazil South America| Goiás Brazil South America|