Neoapaloxylon tuberosum (PROTA)
|Geographic coverage Africa|
|Geographic coverage World|
|Carbohydrate / starch|
Neoapaloxylon tuberosum (R.Vig.) Rauschert
- Protologue: Taxon 31: 559 (1982).
- Family: Papilionaceae (Leguminosae - Papilionoideae, Fabaceae)
- Apaloxylon tuberosum R.Vig. (1949).
Origin and geographic distribution
Neoapaloxylon tuberosum is an endemic species of western and southern Madagascar.
The fibrous bark is used for rope. In the past the bark was used for making bark-cloth. The tuberous root is eaten. The wood is soft and white and is only used as fuelwood.
- Deciduous shrub or small tree up to 13 m tall; bole up to 40 cm in diameter; bark surface smooth and pale grey, with numerous lenticels; twigs glabrous, dark grey, with pale lenticels.
- Leaves alternate, pinnately compound with 10–16 leaflets; stipules minute; petiole and rachis flattened, 4–11 cm long; petiolules 1–1.5 mm long; leaflets alternate, oblong-obovate, (9–)15–30 (–50) mm × 7–15(–20) mm, unequal, glabrous, pinnately veined.
- Inflorescence a panicle, often many together in dense and complex clusters, branches up to 4 cm long, many-flowered.
- Flowers bisexual, regular, greenish white, sessile; hypanthium obconical, 0.5 mm long, resembling a pedicel; sepals 4, free, broadly elliptical, 3–3.5 mm long, concave, with obscure gland dots; petals absent; stamens 10, free, 5–8 mm long; disk prominent, yellow-green; ovary superior, c. 1 mm long, with stipe c. 1 mm long, glabrous, style slender, c. 5 mm long.
- Fruit an indehiscent pod 4.5–6 cm long, with 3–5 mm long stipe, glabrous, pale brown, with a single apical seed and a large basal wing, with persistent sepals at base.
- Seed oblong-ovate, flat, 13–15 mm long, reticulately veined, blackish brown.
Other botanical information
Neoapaloxylon tuberosum flowers when it is leafless and is then very conspicuous because of the profusion of flowers. Flowers appear at the start of the dry winter and fruits mature before the leaves appear. The fruits, which strongly resemble those of maples (Acer) except that the seed is at the apex and the wing at the base, are dispersed by wind. The wing causes the fruit to spin rapidly and fall slowly.
The genus Neoapaloxylon comprises 3 species and the bark of all 3 is used for rope.
Neoapaloxylon madagascariense (Drake) Rauschert is a tree up to 15 m tall.
Neoapaloxylon mandrarense Du Puy & Rabev. is a shrub or small tree 3–5 m tall. The root is eaten.
The genus Neoapaloxylon is very close to another Madagascan endemic genus Brandzeia, which has a single species, Brandzeia filicifolia Baill., a tree of up to 25 m tall that is used for timber.
Neoapaloxylon tuberosum occurs from sea-level up to 900 m altitude in arid to sub-arid, deciduous forest in western and southern Madagascar. It apparently has a preference for limestone soils.
As Neoapaloxylon tuberosum is fairly widespread in Madagascar and apparently not heavily exploited, no major threats of genetic erosion are envisaged.
Neoapaloxylon tuberosum is poorly known and only locally used. It may have potential for ornamental use.
- du Puy, D.J., Labat, J.N., Rabevohitra, R., Villiers, J.-F., Bosser, J. & Moat, J., 2002. The Leguminosae of Madagascar. Royal Botanic Gardens, Kew, Richmond, United Kingdom. 750 pp.
- Rauschert, S., 1982. Nomina nova generica et combinationes novae Spermatophytorum et Pteridophytorum. Taxon 31(3): 554-563.
- Schatz, G.E., 2001. Generic tree flora of Madagascar. Royal Botanic Gardens, Kew, Richmond, United Kingdom. 477 pp.
- Stiles, D., 1998. The Mikea hunter-gatherers of southwest Madagascar: ecology and socioeconomics. African Study Monographs 19(3): 127–148.
- Boiteau, P., Boiteau, M. & Allorge-Boiteau, L., 1999. Dictionnaire des noms malgaches de végétaux. 4 Volumes + Index des noms scientifiques avec leurs équivalents malgaches. Editions Alzieu, Grenoble, France.
- Fougère-Danezan, M., Herendeen, S., Maumont, S. & Bruneau, A., 2010. Morphological evolution in the variable resin-producing Detarieae (Fabaceae): do morphological characters retain a phylogenetic signal? Annals of Botany 105(2): 311–325.
- ILDIS, 2005. World database of Legumes, Version 10,01. International Legume Database & Information Service. [Internet] http://www.ildis.org/. April 2011.
- Lewis, G., Schrire, B., MacKinder, B. & Lock, M., 2005. Legumes of the world. Royal Botanic Gardens, Kew, Richmond, United Kingdom. 577 pp.
- C.H. Bosch, PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands
Correct citation of this article
Bosch, C.H., 2011. Neoapaloxylon tuberosum (R.Vig.) Rauschert. In : Brink, M. & Achigan-Dako, E.G. (Editors). PROTA (Plant Resources of Tropical Africa / Ressources végétales de l’Afrique tropicale), Wageningen, Netherlands. Accessed 7 March 2020.
- See the Prota4U database.