This species occurs in Madagascar.
Horombense is a more compact plant than that of the rosulatum, but has many similarities. The deciduous leaves are narrow, but not as long the rosulatum. The leaves are dark green with a lighter middle vein and form a rosette around the tips of branches. The trunk is smooth with conical spines and is greenish silver. Branching occurs more frequently and may start from the base. This species has larger yellow flowers in clusters on fairly long peduncles. Flowers will set in the second or third year in good conditions. Horombense should be given full light and plenty of water during the warmer months and considerably less water in the cool months. Seedlings grow fairly slowly compared to other Pachypodium species.