Rhytidocaulon is a plant genus 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 Members of the ...

, first described in 1962. It is native to northeastern

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

and the

Arabian Peninsula The Arabian Peninsula, (; ar, شِبْهُ الْجَزِيرَةِ الْعَرَبِيَّة, , "Arabian Peninsula" or , , "Island of the Arabs") or Arabia, is a peninsula of Western Asia, situated northeast of Africa on the Arabian Plate ...

;SpeciesThe Plant List, ''Rhytidocaulon''
/ref> # '' Rhytidocaulon paradoxum'' P.R.O.Bally - Ethiopia # '' Rhytidocaulon piliferum'' Lavranos - Somalia # '' Rhytidocaulon richardianum'' Lavranos - Somalia # '' Rhytidocaulon subscandens'' P.R.O.Bally - Somalia, Ethiopia # ''

Rhytidocaulon tortum Rhytidocaulon is a plant genus in the family Apocynaceae, first described in 1962. It is native to northeastern Africa and the Arabian Peninsula ;Species # '' Rhytidocaulon paradoxum'' P.R.O.Bally - Ethiopia # '' Rhytidocaulon piliferum'' Lavran ...

'' (N.E.Br.) M.G.Gilbert - Arabia ;species with undetermined affinities ;Taxonomy Phylogenetic studies have shown the genus to be monophyletic, and most closely related to the genus ''

Echidnopsis ''Echidnopsis'' is a genus of succulent, cactus-like plants in the family Apocynaceae, first described as a genus in 1871. They are native to eastern Africa and the Arabian Peninsula. ;Accepted species ;Species formerly included ''Echidnopsi ...

'' which inhabits the same region. Marginally more distantly related is a sister branch comprising the genus ''

Pseudolithos ''Pseudolithos'' is a genus of succulent flowering plants of the family Apocynaceae, indigenous to arid areas of Somalia, Yemen and Oman. Description and naming The plants were first described as a genus in 1965; the name ''"Pseudo-lithos"'' me ...

'' and the widespread ''

Caralluma ''Caralluma'' is a genus of flowering plants in the family Apocynaceae, consisting of about 120 species. In 1795 William Roxburgh published the name '' Stapelia adscendens'' for a plant found in India. He commented that the name for the plant ...

'' stapeliads of North Africa.P. Bruyns, C. Klak, P. Hanacek: ''Evolution of the stapeliads (Apocynaceae-Asclepiadoideae) - repeated major radiation across Africa in an Old World group. Molecular Phylogenetics and Evolution.'' 2014. v. 77, no. 1, p. 251--263. ISSN 1055-7903.

References

{{Taxonbar, from=Q3429900 Apocynaceae genera Asclepiadoideae