Corryocactus is a genus of columnar cacti in the family Cactaceae (order Caryophyllales), described in 1920 by American botanists Nathaniel Lord Britton and Joseph Nelson Rose in their monograph The Cactaceae. The genus is native to the high-altitude regions of Bolivia, Peru, and northern Chile, where most species grow between 2,000 and 3,000 meters elevation, with some occurring in lowlands or ascending as high as 4,000 meters.
Plants in this genus branch profusely from the base and have fibrous or, in some species, tuberous root systems. Growth habit varies widely across the genus: smaller species tend to be erect, while larger ones may be prostrate with upright tips, sprawl or climb over surrounding vegetation, or start out erect before drooping. Stems are typically 2 to 5 cm thick, though at least one species forms tall columns up to 5 meters high with stems 10 to 15 cm in diameter. The stems bear 4 to 10 ribs that swell at the areoles, which are tuberculate and heavily armed with spines; central spines usually measure 3 to 5 cm but occasionally reach 15 cm or even 25 cm in length.
Flowers arise singly from the areoles and open during the day, with short tubes and blooms 2 to 10 cm across. Perianth color spans yellow, orange, and red, and can vary even within a single species. After fertilization, the plants produce spiny, spherical fruits 3 to 10 cm in diameter containing dark brown to black seeds suspended in juicy pulp.
Taxonomically, Corryocactus has moved between tribal placements over time — it has been classified in Notocacteae and in Echinocereeae, but a 2011 molecular phylogenetic study found it fell outside the well-supported "core" Echinocereeae clade. Several other genus names, including Corryocereus, Erdisia, and Eulychnocactus, have been synonymized into Corryocactus. The genus name itself honors Thomas Avery Corry, an engineer with the Peruvian railway company Ferrocarril del Sur whose railway construction work led to the discovery of the first three known species.
Etymology
The genus name Corryocactus honors Thomas Avery Corry (1862–1942), an engineer for the Peruvian railway company Ferrocarril del Sur, whose work laying a new railway line led to the discovery of the first three known species.
Distribution
Corryocactus occurs in Bolivia, Peru, and northern Chile. Most species grow at altitudes of 2,000–3,000 m, though some are found in lowlands or up to 4,000 m.
Taxonomy Notes
Described by Britton & Rose in 1920 (The Cactaceae 2: 66), the genus has been placed in tribe Notocacteae and later in Echinocereeae, but a 2011 molecular phylogenetic study excluded it from the "core" Echinocereeae clade. Corryocereus, Erdisia, and Eulychnocactus are treated as synonyms of Corryocactus.
