''Opuntia galapageia'' is a species of

cactus A cactus (, or less commonly, cactus) is a member of the plant family Cactaceae, a family comprising about 127 genera with some 1750 known species of the order Caryophyllales. The word ''cactus'' derives, through Latin, from the Ancient Greek ...

. It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to the

Galápagos Islands The Galápagos Islands (Spanish: , , ) are an archipelago of volcanic islands. They are distributed on each side of the equator in the Pacific Ocean, surrounding the centre of the Western Hemisphere, and are part of the Republic of Ecuador ...

, part of

Ecuador Ecuador ( ; ; Quechua: ''Ikwayur''; Shuar: ''Ecuador'' or ''Ekuatur''), officially the Republic of Ecuador ( es, República del Ecuador, which literally translates as "Republic of the Equator"; Quechua: ''Ikwadur Ripuwlika''; Shuar: ''Eku ...

. Forms occurring on different islands have been treated as separate species and subtaxa of these species. ''Opuntia echios'', ''Opuntia helleri'', ''Opuntia insularis'', ''Opuntia megasperma'', ''Opuntia myriacantha'' and ''Opuntia saxicola'' are now sunk within ''O. galapageia''.

Taxonomy

''Opuntia galapageia'' was first described by

John Stevens Henslow John Stevens Henslow (6 February 1796 – 16 May 1861) was a British priest, botanist and geologist. He is best remembered as friend and mentor to his pupil Charles Darwin. Early life Henslow was born at Rochester, Kent, the son of a solicit ...

in 1837. It was first recorded by

Charles Darwin Charles Robert Darwin ( ; 12 February 1809 – 19 April 1882) was an English naturalist, geologist, and biologist, widely known for his contributions to evolutionary biology. His proposition that all species of life have descended fr ...

on Santiago (James) Island. Darwin was ashore there for nine days in 1835. Subsequently, at least five other species of ''Opuntia'' were described from the Galápagos: ''Opuntia helleri'', ''Opuntia insularis'', ''Opuntia megasperma'', ''Opuntia myriacantha'' and ''Opuntia saxicola''. All were treated by David Hunt in 2006 as included within ''O. galapageia'', a placement accepted by the

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...

as of 2017, although they had been assessed as separate species in 2000.

Plants of the World Online Plants of the World Online (POWO) is an online database published by the Royal Botanic Gardens, Kew. It was launched in March 2017 with the ultimate aim being "to enable users to access information on all the world's known seed-bearing plants by ...

also accepts the placement within ''O. galapageia'', and includes ''Opuntia echios'', in most cases placing the species in an infraspecific taxon (see the list below).

Infraspecific taxa

A large number of varieties and other infraspecific taxa have been named. ,

accepts the following: Two other infraspecific taxa that have been named are not recognized by Plants of the World Online as distinct from the species: *''Opuntia galapageia'' var. ''brossettii'' Backeb. *''Opuntia galapageia'' subvar. ''orientalis'' (J.T.Howell) Backeb.

Distribution

''Opuntia galapageia'' is

to the

. Forms occurring on different islands have been described as subtaxa of the species (see the list above). Island distributions given by Plants of the World Online include: * Fernandina **''O. galapageia'' var. ''insularis'' * Isabela **''O. galapageia'' subvar. ''inermis'' **''O. galapageia'' var. ''insularis'' **''O. galapageia'' var. ''profusa'' **''O. galapageia'' var. ''saxicola'' * Seymour **''O. galapageia'' var. ''zacana'' * Pinzon **''O. galapageia'' var. ''macrocarpa'' * Santa Cruz **''O. galapageia'' var. ''gigantea'' * Santa Fe **''O. galapageia'' subvar. ''barringtonensis'' *

Santiago Santiago (, ; ), also known as Santiago de Chile, is the capital and largest city of Chile as well as one of the largest cities in the Americas. It is the center of Chile's most densely populated region, the Santiago Metropolitan Region, whose ...

**''O. galapageia'' var. ''profusa''

References

galapageia Flora of the Galápagos Islands Cacti of South America Taxonomy articles created by Polbot {{Cactus-stub