Total: 3
The smallest species in the genus with a flattened, tuberous caudex 2-8cm tall and up to 40cm in diameter, resembling a rock or cluster of potatoes. Virtually branchless with sparse leaves in rosettes. Produces bright yellow trumpet-shaped flowers. Strictly adapted to acidic substrates with pH 3.5-4.5.
A caudiciform succulent with a swollen, balloon-shaped silvery-gray caudex up to 40cm in diameter. The plant reaches up to 90cm in height with slender reddish-brown branches bearing paired spines. Produces bright yellow, fragrant flowers on long peduncles. Leaves are narrow and deciduous during the dry season.
A pachycaul succulent shrub or small tree with a swollen caudex that stores water. Grows 2-4m tall in habitat. Produces clusters of trumpet-shaped flowers primarily in pink and red shades. Evergreen or drought-deciduous depending on conditions. Contains cardiac glycosides in all parts, making it highly toxic if ingested.