Origin and Habitat: South-western part of Madagascar
Habitat and ecology: Jatropha mahafalensisSN|34831]]SN|34831]] is widespread in the arid bush of the south-west of the island, especially on limestone. This is the only naturally occurring representative of the genus in Madagascar. In Madagascar J.mahafalensis is commonly cultivated.

• Jatropha mahafalensis Jum. & H.Perrier

Description: Jatropha mahafalensisSN|34831]]SN|34831]] is a large dioecious shrub or small much-branched tree, to 5-6 m tall. It grows a thick, attractive trunk and small, glossy, three-lobed leaves. This species differs from the others of the genus in being dioecious.
Derivation of specific name. The epithet “mahafalensis” comes from the occurrence in the Mahafaly region, south-western part of Madagascar .
Stem: Thick, much branched from near the base, young branches softly woody, sap becoming brown.
Leaves: 3- to 5-lobed, large up to 6 cm long, 8 cm wide, lobes triangular. Petiole to 8 cm long.
Inflorescences: Few-flowered terminal or subterminal cymes on peduncles 1 cm long.
Flowers: Creamy-white, basally red stripped. Male flowers with sepals 6 mm long, joined for 2.5 mm, petals obovate, 9 mm long, yellow streaked red, nectar-glands 5, stamens 8. Female flowers with sepals shortly joined, triangular, petals larger than male, to 13 long and 7 mm wide, style 3 mm long.
Fruits: Large (ca. 25 mm in diameter), green drupaceous capsules.
Seeds: Broadly ovoid, 15 mm long, laterally compressed, to 15 x 10 mm.
Chromosome number: 2n=22
Taxonomy: J. mahafalensi is the only species of the genus native to Madagascar and is distinct taxonomically—Radcliffe-Smith erected the monotypic subgenus Manihotoides to accommodate it.

Bibliography: Major references and further lectures
1) Gabriella Harriet Schmelzer “Medicinal Plants”, Volume 1 PROTA, 2008
2) Werner Rauh, Herman Schwartz “Succulent and xerophytic plants of Madagascar”, Volume 2, Strawberry Press, 1998
3) Urs Eggli “Illustrated Handbook of Succulent Plants: Dicotyledons” Springer Science & Business Media, 2002
4) NIIR Board of Consultants and Engineers “The Complete Book on Jatropha (Bio-Diesel) with Ashwagandha, Stevia, Brahmi & Jatamansi Herbs (Cultivation, Processing & Uses)” ASIA PACIFIC BUSINESS PRESS Inc., 1 October 2008
5) JUMELLE, H. “Un Jatropha dioique de Madagascar. [A dioecious Jatropha from Madagascar.]” Rev. Gen. Botany 32: 121-124. 1920.
6) Urs Eggli, Leonard E. Newton “Etymological Dictionary of Succulent Plant Names” Springer Science & Business Media, 29 June 2013
7) "Jatropha mahafalensis oil from Madagascar: Properties and suitability as liquid biofuel" (PDF Download Available). Available from: https://www.researchgate.net/publication/251571733_Jatropha_mahafalensis_oil_from_Madagascar_Properties_and_suitability_as_liquid_biofuel [accessed Jan 31 2018].
8) International Succulent Introductions of the Huntington Botanical Gardens “ISI 2005-28. Jatropha mahafalensis Jum. & Perr.” Published in the Cactus and Succulent Journal, Vol. 77 (2), March - April, 2005 web: http://www.huntington.org/botanicaldiv/isi/ISI2005/2005-28.html
9) Fiche: Jatropha mahafalensis Jum. & H. Perrier, 1910 web: http://www.xycol.net/index.php?categorie=200&op=fiche&appellation_nsr=Jatropha+mahafalensis+Jum.+%26+H.+Perrier%2C+1910&appellationannee=%MTkxMA==%&via=Histographe

Cultivation and Propagation: Uses: The seeds of Jatropha mahafalensisSN|28980]]SN|34831]] Jum. & H.Perrier, endemic to Madagascar, contain an oil called 'huile de Betrata' with similar proper-ties as Jatropha curcasSN|34831]]SN|28980]] and with similar traditional uses. The oil is also used for lighting and applied as hair oil against lice. A root decoction is taken as an invigorating drink. J. mahafalensis oil is suitable for biodiesel production in combustion engines, but filtration or degumming are needed to reduce its element content prior to such use.