Trees or shrubs. Leaves opposite, palmate, rarely simple. Inflorescence of terminal spikes, panicles, dense heads or umbels. Calyx unequally 2-5-lobed. Corolla funnel-shaped or funnel-shaped-campanulate, showy, yellow, white, pink, red or purple, slightly 2-lipped. Stamens 4. Fruit a linear-oblong, pendulous capsule. Seeds winged.
Barcode of Life Data Systems (BOLD) Stats Specimen Records:101 Specimens with Sequences:135 Specimens with Barcodes:124 Species:22 Species With Barcodes:21 Public Records:62 Public Species:17 Public BINs:0
All of the species in the first two columns below were recognized and described by Gentry in 1992. Listed in the third column are species names that have been used recently, but were not accepted by Gentry. The currently accepted synonym for each is in parentheses.
Seeds thin, with 2 wings; wings hyaline, membranaceous, and sharply demarcated from the seed body.
Tabebuia is distinguished from Handroanthus by wood that is not especially hard or heavy, and not abruptly divided into heartwood and sapwood. Lapachol is absent. Scales are present, but no hair. The calyx is usually spathaceous in Tabebuia, but never so in Handroanthus. Only two species of Tabebuia are yellow-flowered, but most species of Handroanthus are.
Unlike Roseodendron, the calyx of Tabebuia is always distinctly harder and thicker than the corolla. Tabebuia always has a dichotomously branched inflorescence; never a central rachis as in Roseodendron. Some species of Tabebuia have ribbed fruit, but not as conspicuously so as the two species of Roseodendron.
The wood of Tabebuia is light to medium in weight. Tabebuia rosea (including T. pentaphylla) is an important timber tree of tropical America.Tabebuia heterophylla and Tabebuia angustata are the most important timber trees of some of the Caribbean islands. Their wood is of medium weight and is exceptionally durable in contact with salt water.
The swamp species of Tabebuia have wood that is unusually light in weight. The most prominent example of these is Tabebuia cassinoides. Its roots produce a soft and spongy wood that is used for floats, razor straps, and the inner soles of shoes.
In spite of its use for lumber, Tabebuia is best known as an ornamental flowering tree. Tabebuia aurea, Tabebuia rosea, Tabebuia pallida, Tabebuia berteroi, and Tabebuia heterophylla are cultivated throughout the tropics for their showy flowers.Tabebuia dubia, Tabebuia haemantha, Tabebuia obtusifolia, Tabebuia nodosa, and Tabebuia roseo-alba are also known in cultivation and are sometimes locally abundant.
Tabebuia heteropoda, Tabebuia incana, and other species are occasionally used as an additive to the entheogenic drink Ayahuasca.
Pau d'arco is promoted as a treatment for a number of human ailments, including cancer. According to the American Cancer Society, "available evidence from well-designed, controlled studies does not support this substance as an effective treatment for cancer in humans", and using it risks harmful side-effects.
Handroanthus was established by Joáo Rodrigues de Mattos in 1970. Gentry did not agree with the segregation of Handroanthus from Tabebuia and warned against "succumbing to further paroxysms of unwarranted splitting". In 1992, Gentry published a revision of Tabebuia in Flora Neotropica, in which he described 99 species and 1 hybrid, including those species placed by some authors in Roseodendron or Handroanthus. Gentry divided Tabebuia into 10 "species groups", some of them intentionally artificial. Tabebuia, as currently circumscribed, consists of groups 2,6,7,8,9, and 10. Group 1 is now the genus Roseodendron. Groups 3,4, and 5 compose the genus Handroanthus.
Roseodendron was resolved as sister to a clade consisting of Handroanthus and four other genera. This result had only weak statistical support, but Roseodendron clearly did not group with the remainder of Tabebuia. Consequently, Roseodendron was resurrected in its original form. The remaining 67 species of Tabebuia formed a strongly supported clade that is sister to Ekmanianthe, a genus of two species from Cuba and Hispaniola. Tabebuia had been traditionally placed in the tribeTecomeae, but that tribe is now defined much more narrowly than it had been, and it now excludes Tabebuia.Tabebuia is now one of 12 to 14 genera belonging to a group that is informally called the Tabebuiaalliance. This group has not been placed at any particular taxonomic rank.
^Eberhard Fischer, Inge Theisen, and Lúcia G. Lohmann. 2004. "Bignoniaceae". pages 9-38. In: Klaus Kubitzki (editor) and Joachim W. Kadereit (volume editor). The Families and Genera of Vascular Plants volume VII. Springer-Verlag: Berlin; Heidelberg, Germany. ISBN 978-3-540-40593-1
^David J. Mabberley. 2008. Mabberley's Plant-Book third edition (2008). Cambridge University Press: UK. ISBN 978-0-521-82071-4
^ abcSusan O. Grose and Richard G. Olmstead. 2007. "Evolution of a Charismatic Neotropical Clade: Molecular Phylogeny of Tabebuia s.l., Crescentieae, and Allied Genera (Bignoniaceae)". Systematic Botany 32(3):650-659. doi:10.1600/036364407782250553
^ abGeorge W. Staples and Derral R. Herbst. 2005. "A Tropical Garden Flora" Bishop Museum Press: Honolulu, HI, USA. ISBN 978-1-58178-039-0
^ abcdeAlwyn H. Gentry. 1992. "Bignoniaceae: Part II (Tribe Tecomeae)". Flora Neotropica Monograph 25(part 2):1-373.
^ abTabebuia in International Plant Names Index. (see External links below).
^Samuel J. Record and Robert W. Hess. 1940. "American timbers of the family Bignoniaceae". Tropical Woods 63:9-38.
^ abAlwyn H. Gentry. 1992. "A Synopsis of Bignoniaceae Ethnobotany and Economic Botany". Annals of the Missouri Botanical Garden 79(1):53-64.
^Anthony Huxley, Mark Griffiths, and Margot Levy (1992). The New Royal Horticultural Society Dictionary of Gardening. The Macmillan Press,Limited: London. The Stockton Press: New York. ISBN 978-0-333-47494-5 (set).
^ abLuciana Baza Mendonça & Luiz dos Anjos (2005): Beija-flores (Aves, Trochilidae) e seus recursos florais em uma área urbana do Sul do Brasil [Hummingbirds (Aves, Trochilidae) and their flowers in an urban area of southern Brazil]. [Portuguese with English abstract] Revista Brasileira de Zoologia 22(1): 51–59. doi:10.1590/S0101-81752005000100007PDF fulltext
^Augustin Pyramus de Candolle. 1838. "Revue sommaire de la famille des Bignoniaceae". Bibliotheque Universelle de Genève, series 2, 17:130.
^Tabebuia In: Index Nominum Genericorum. In: Regnum Vegetabile (see External links below).
^Nathaniel Lord Britton. 1915. "Studies of West Indian plants". Bulletin of the Torrey Botanical Club 42(7):372-379.
^George Bentham and Joseph D. Hooker. 1876. Genera plantarum :ad exemplaria imprimis in Herberiis Kewensibus servata definita vol. 2 part 2:1026-1053. Reeve & Co. London, England. (See External links below).
^Faustino Miranda-Gonzalez. 1965. "Estudios acerca de arboles y arbustos de America Tropical principamente de Mexico". Boletin de la Sociedad Botanica de Mexico 29( ):34-49.
^Russell J. Seibert. 1940. "New names in Cybistax and Tabebuia". Tropical Woods 63:7-8.
^Joáo Rodrigues de Mattos. 1970. "Handroanthus, Um novo gênero para os "ipês" do Brasil". Loefgrenia 50(?):1-4.
^Alwyn H. Gentry. 1972. "Handroanthus (Bignoniaceae): A critique". Taxon 21(1):113-114.
^Richard G. Olmstead, Michelle L. Zjhra, Lúcia G. Lohmann, Susan O. Grose, and Andrew J. Eckert. 2009. "A molecular phylogeny and classification of Bignoniaceae". American Journal of Botany 96(9):1731-1743. doi:10.3732/ajb.0900004