''Stapelianthus'' is a genus of

flowering plant Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (). The term angiosperm is derived from the Ancient Greek, Greek words (; 'container, vessel') and (; 'seed'), meaning that the seeds are enclosed with ...

s in the family

Apocynaceae Apocynaceae (, from '' Apocynum'', Greek for "dog-away") is a family of flowering plants that includes trees, shrubs, herbs, stem succulents, and vines, commonly known as the dogbane family, because some taxa were used as dog poison. Notable mem ...

, first described as a genus in 1933. The entire genus is endemic to

Madagascar Madagascar, officially the Republic of Madagascar, is an island country that includes the island of Madagascar and numerous smaller peripheral islands. Lying off the southeastern coast of Africa, it is the world's List of islands by area, f ...

and is concentrated in the far south of the island. The genus is defined by the unique corona structure of its flowers.

Species

Species accepted by the

Plants of the World Online Plants of the World Online (POWO) is an online taxonomic database published by the Royal Botanic Gardens, Kew. History Following the Convention on Biological Diversity, the Royal Botanic Gardens in Kew launched Plants of the World Online i ...

as of January 2023 ;formerly includedThe Plant List
/ref> # ''Stapelianthus baylissii'', syn of '' Tridentea baylissii'' # ''Stapelianthus choananthus'', syn of '' Tridentea choanantha'' ;Taxonomy The species are extremely close to each other genetically, however the genus overall is very divergent from its relatives on the mainland. Phylogenetic studies have shown the genus to be most closely related to a large and widespread branch of stapeliads from mainland Africa, comprising the genera '' Huernia'', '' Tavaresia'' and a mixed sub-branch including '' Orbea'', '' Piaranthus'' and ''

Stapelia ''Stapelia'' is a genus of low-growing, spineless, stem succulent plants, predominantly from South Africa with a few from other parts of Africa. Several Asian and Latin American species were formerly included but they have all now been transfer ...

''.

References

Apocynaceae genera Endemic flora of Madagascar Asclepiadoideae {{Apocynaceae-stub