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

Pseudolithos
Pseudolithos migiurtinus plant in cultivation
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Asterids
Order: Gentianales
Family: Apocynaceae
Subfamily: Asclepiadoideae
Tribe: Ceropegieae
Genus: Pseudolithos
P.R.O.Bally

Description and naming

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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]

Species [4]
  1. Pseudolithos caput-viperae Lavranos - Somalia
  2. Pseudolithos cubiformis (P.R.O. Bally) P.R.O. Bally - N Somalia
  3. Pseudolithos dodsonianus (Lavranos) Bruyns & Meve - Somalia & Oman
  4. Pseudolithos gigas Dioli - Eastern Ethiopia
  5. Pseudolithos harardheranus Dioli - Somalia
  6. Pseudolithos horwoodii P.R.O. Bally & Lavranos - Somalia
  7. Pseudolithos mccoyi Lavranos - Yemen & Oman
  8. Pseudolithos migiurtinus (Chiov.) P.R.O. Bally - S + C Somalia
  9. Pseudolithos sphaericus (P.R.O. Bally) P.R.O. Bally - N Somalia

Taxonomy

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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]

References

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  1. ^ Bally, P. R. O.; Horwood, F. K.; Lavranos, J. J. (1975). "A Monograph of the Genera Pseudolithos and Whitesloanea". The National Cactus and Succulent Journal. 30 (2): 31–36. ISSN 0027-8858. JSTOR 42791977.
  2. ^ "Tropicos - Name - Pseudolithos P.R.O. Bally". tropicos.org.
  3. ^ "Notes Pseudolithos - Quaqua". asclepiad-exhibition.org.
  4. ^ "Pseudolithos". Plants of the World Online. Royal Botanic Gardens, Kew.
  5. ^ 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.
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