Monographs Details:
Authority:

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

Fabaceae
Synonyms:

Possira arborescens Aubl., Possira triphylla Sw., Rittera dodecandra Vahl, Swartzia dodecandra (Vahl) Willd., Swartzia triphyllata Willd., Swartzia parviflora DC., Swartzia bifida Steud., Tounatea arborescens (Aubl.) Britton, Tunatea arborescens (Aubl.) Kuntze, Tounatea dodecandra (Vahl) Taub., Tunatea dodecandra (Vahl) Kuntze, Swartzia rariflora Hoehne
Description:

Description - Shrub or tree 6-23 m tall, the trunk fluted basally, 8-30 cm diameter, the branchlets slender, pilosulose to strigulose, sometimes densely so, often glabrescent; stipules usually persistent, (2-)4-6(-10) mm long, 0.3-1 (-2) mm wide, subulate, acute, strigulose externally, soon glabrescent; petioles (4-) 10-15(-20) mm long, usually obviously winged, the wing oblong-oblanceolate, shorter than the petioles, stipellate at the apex, the wing glabrous but the axis pilosulose, the rachis (l-)2-3 (-4) cm long, usually obviously narrowly alate, the wing linear to oblanceolate-oblong narrowly, to 5 mm wide, glabrous, the axis pilosulose; leaflets 1- or 2-(-3-) jugate, sometimes some of the leaves unifoliolate, the petiolules (0.5-) 1-3 mm long, strigulose to pilosulose, or infrequently glabrous, the blades of the lateral leaflets (2-)4-6(-7.5) cm long, (1 -)2-3.5 cm wide, usually ovate to lanceolate, the terminal blade (4-)7-12(-15) cm long, (1.5-)3-5(-6) cm wide, usually elliptic, the base of all the blades rounded-obtuse to acute, the apex usually acuminate, or acute with the tip retuse or sometimes only obtuse or truncate, glabrous or strigulose or pilosulose on the costa either on both sides of the blade or only beneath, the venation salient on both sides or only the costa salient, the primary veins often plane; inflorescences axillary, (2-)3-5(-8) cm long, the axis sparingly strigulose, the peduncle (3-)6-12(-28) mm long, the rachis (6-)10-20(-30) mm long, the bracts caducous to deciduous, ca 1 mm long, densely strigulose, sometimes the bracts foliaceous, 1-3-foliolate, the leaflets to 4 mm long, the bracteoles persistent, subulate, 1-2.5 mm long, glabrous to strigulose; pedicels (9-) 12-15(-30) mm long, glabrous, the buds globose, 3-4 mm diameter; calyx segments 3 or 4, deciduous, glabrous; petal yellow, glabrous, the claw 1-2 mm long, the blade rounded, 3-6.5 mm diameter; stamens isomorphic, 10-15 apparently functional, ca 15 staminodia, all glabrous, the filaments of the fertile stamens (6-)8-12 mm long, the anthers more or less orbicular, 0.5-0.7 mm diameter, the pollen globose, ca 26 /i diameter; gynoecium glabrous, the stigma capitellate, the style 1-3 mm long, the ovary narrowly oblong-elliptic, often arcuate, 3-7.5 mm long, 1-1.5 mm wide, the gynophore 2-5 mm long; fruit glabrous, elliptic in outline, compressed laterally, 3-4.5(-6.5) cm long, 1.5-2.5 cm wide, the stipe 3-17 mm long; seeds 1 per fruit.

Discussion:

I have seen statements and a few collection records which indicate that this species is also in Central America and the West Indies; there is a sheet in the herbarium at Stockholm and at Copenhagen of a collection supposedly made by John Ryan in the West Indies. Since there are no other records of the species north of Venezuela, I suspect that the Ryan material is actually a duplicate received from von Rohr, who was a friend of Ryan. Von Rohr’s collection came from somewhere in French Guiana and was the basis for S. dodecandra Vahl. Reports of the species outside the distribution given above are probably based on misidentifications.

As with most widespread species in this family in northern South America, there is some variation and consequently an extensive synonomy. Aside from the superfluous names of Swartz and Willdenow, the other specific epithets were given usually without mention of the earlier one, the new species being based on some variant in the population. De Candolle’s S. parviflora was based on material with small petals and unifoliolate leaves; he compared his type with Aublet’s plate of Possira arborescens and concluded that a different species was involved. Hoehne’s name is based on rather fragmentary material which does appear to be uniformly unifoliolate; however, unifoliolate leaves are not common in the rest of the collections, although the leaves are predominantly trifoliolate.

There appears to be in the genus an evolutionary pressure toward reduction in the number of stamens, especially the larger ones; in S. arborescens this process is well-advanced, for not only are there no large stamens present in the flowers, the number of smaller ones is less than in most of the species. Only in S. auriculata has the androecium been so reduced; this is the nearest relative of the present species and differs from it in that the leaves are unifoliolate, and the flowers larger.
Distribution:

Colombia South America| Meta Colombia South America| Vaupés Colombia South America| Amazonas Colombia South America| Putumayo Colombia South America| Venezuela South America| Bolívar Venezuela South America| Amazonas Venezuela South America| Guyana South America| Suriname South America| French Guiana South America| Peru South America| San Martín Peru South America| Loreto Peru South America| Bolivia South America| Brazil South America| Amazonas Brazil South America| Amapá Brazil South America| Pará Brazil South America| Rio de Janeiro Brazil South America|

Common Names:

Alanjahoedoe, bobinzana amarilla, e-né-goo-hee-ro-ma, guamo, orangehout, serebedan, waremapan-soela