Pseudolithos

Pseudolithos
Pseudolithos migiurtinus plant in cultivation
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Asterids
Order:	Gentianales
Family:	Apocynaceae
Subfamily:	Asclepiadoideae
Genus:	Pseudolithos P.R.O.Bally

Pseudolithos is a genus of succulent flowering plants of the family Apocynaceae, indigenous to Somalia, Yeman and Oman.

The plants were first described as a genus in 1965; the name "Pseudo-lithos" means "false-stone" and refers to their pebble-like appearance. All species in this genus are highly succulent, highly reduced, and exhibit tessellation on their stems' surface. Their small flowers appear on the spherical body's surface.

Phylogenetic studies have shown the genus to be monophyletic, and most closely related to the widespread Caralluma stapeliads of North Africa. Marginally more distantly related is a sister branch comprising the genera Echidnopsis and Rhytidocaulon.

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