Pachypodium ambongense is a species of plant in the family Apocynaceae. It was first published as a species of the genus Pachypodium in 1924 by the botanist Henri Louis Poisson.
Origin and Habitat: Pachypodium ambongense is endemic to Madagascar, it has a very localised habitat in the area of the river Ambonho (Ambongo) on the tsingy at Namoroka Reserve about 200 km north of Bemaraha in the Province of Mahajanga. It is known only from 2-5 localities.
Type locality: Madagascar, Majunga (— Mahajanga), Namoroka Reserve.
Elevation range: about 100 metres above sea level.
Habitat: Pachypodium ambongense grows in open deciduous dry forests in crevices filled with black humus on inselberg and limestone rock faces. In the same area it is possible to find several endemic succulents and xerophyte plants such as: Uncarina perrieri, Uncarina sakalava, Pachypodium rutenbergianum and sveral species of Euphorbia, Commiphora, Cyphostemma and Lomatophyllum. This is a very hot area, the annual average temperature is 27 ° C. Thermometer never shows less than 10 – 11 ° C, but can show up to 40° C. Rainfall is 1300 mm per year, the dry season lasts 7 months.
