Sprucina Nied., Arbeiten Bot. Inst. Königl. Lyceum Hosianum Braunsberg 3: 18. 1908.—No combinations were ever published in this genus. The syntypes are the sheets of Spruce 2853 (Amazonas, Brazil) at BR, G, and W; they are referable to Jubelina grisebachiana W. R. Anderson.
Diplopterys sect. Eujubelina Nied., Arbeiten Bot. Inst. Königl. Lyceum Hosianum Braunsberg 4: 17. 1912.—Syntypes: D. uleana Nied. [J. uleana (Nied.) Cuatrec.], D. rosea (Miq.) Nied. [J. rosea (Miq.) Nied.], D. bracteosa (Griseb.) Nied. [Malpighiodes bracteosa (Griseb.) W. R. Anderson], and D. riparia (Adr. Juss.) Nied. [J. riparia Adr. Juss.].
Woody vines. Petiole eglandular; lamina bearing glands impressed in the abaxial surface or rarely eglandular, the lateral veins prominent below and interconnected by ± parallel "scalariform" tertiary veins; stipules small or minute, triangular, borne on base of petiole. Inflorescences axillary and terminal, decompound, containing much-reduced bractlike leaves below the floriferous bracts, the flowers ultimately borne in umbels of 4 or corymbs of 6; bracts and bracteoles large, pubescent on both sides, eglandular; floriferous peduncle well developed. Sepals not completely concealing petals during enlargement of bud, revolute or reflexed in anthesis, narrowly ovate, the anterior eglandular, the lateral 4 each usually bearing 1 large abaxial gland formed by ± complete fusion of 2 (except in J. uleana, with 6–8 distinct glands), occasionally all sepals eglandular; corolla bilaterally symmetrical, the posterior petal different from lateral 4; petals pink, violet, or yellow, at least the anterior-lateral 2 abaxially sericeous; androecium bilaterally symmetrical; stamens glabrous; filaments proximally connate, very stout opposite posterior-lateral petals; anthers ± alike; gynoecium bilaterally symmetrical; ovary with the carpels completely connate; styles stout, the apex with a large internal stigma and dorsally truncate or short-hooked. Samaras separating from a high pyramidal torus; samara orbicular or transversely elliptical, the lateral wings cleft to nut at apex, usually confluent at base, each lateral wing with a complex structure comprising at least an outer membranous wing and a sterile cavity developed in its base, parallel to the fertile locule, during maturation of the fruit, and frequently bearing additional wings, winglets, crests, or irregular outgrowths between outer wing and central dorsal wing; dorsal wing often extended forward at apex between lateral wings; ventral areole narrowly elliptical or linear. Chromosome number: n = 10 (J. magnifica; W. R. Anderson, 1993a); photo.
Six species of Central America and northern South America, in tropical wet primary and secondary forests from near sea level to 1000 m; J. grisebachiana is also reported to occur in open areas. [map] — Regional key to genera: Central America.
Jubelina is distinguished by the following combination of character-states: laminas with scalariform tertiary veins and glands impressed in the abaxial surface, large decompound inflorescences with the flowers in umbels or corymbs of 4–6, large bracts and bracteoles, long narrow sepals, at least the two outermost petals abaxially sericeous, and samaras with complex lateral wings, each of which contains a sterile cavity parallel to the fertile locule and usually at least one crest or wing between the outer lateral wing and the central dorsal wing. Five of the six species are notable for having the paired calyx glands (if present) connate to form one large gland in the center of the sepal (see also discussion of Mezia). The sterile cavities in the samaras suggest adaptation for dispersal by water as well as wind, and in two species (J. magnifica W. R. Anderson and J. riparia) the wings have become reduced or replaced by ruffles, probably signifying a shift from dispersal primarily by wind to dispersal primarily by water (W. R. Anderson, 1990a). Four of the six species (J. riparia, J. rosea, J. uleana, and J. wilburii) are included in the latest sampling of DNA sequences (Davis & Anderson, 2010 [pdf]), and the bootstrap support for the genus is 89%.
Etymology: The name Jubelina honors Jean Guillaume Jubelin, 1787–1860, who served as governor of French Guiana for most of the seven years from 1829 to 1836. Jussieu was recognizing Jubelin's support of scientific researchers such as F. M. R. Leprieur, who collected the type of Jubelina riparia in French Guiana during Jubelin's tenure as governor and sent it to the herbarium in Paris, where it came to Jussieu's attention.