Pseudolithos is a genus of succulent flowering plants of the family Apocynaceae, indigenous to arid areas of Somalia, Yemen 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. It was originally proposed as Lithocaulon earlier in 1956, but this name was already in use for a genus of fossil algae.[1] All species in this genus are highly succulent, small in size, and exhibit tessellation on their stems' surface. Their small flowers appear on the spherical body's surface.[2][3]
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.[5]
Pseudolithos is a genus of succulent flowering plants of the family Apocynaceae, indigenous to arid areas of Somalia, Yemen and Oman.