Strophocactus brasiliensis

Strophocactus brasiliensis, synonym Pseudoacanthocereus brasiliensis, is a species of plant in the family Cactaceae. It is endemic to Brazil. Its natural habitats are subtropical or tropical dry forests and hot deserts. It is threatened by habitat loss.

Description
Strophocactus brasiliensis grows as a shrub, later spreading to prostrate, shiny, bright green shoots, initially upright and later sprawling. It branches freely. The thin stems are up to 3 cm across and have 2–7 ribs bearing small areoles with many needle-like spines 2 to 4 centimeters apart. The small areoles are From them arise numerous needle-like, white thorns that have a darker tip and are up to 3 centimeters long. The white funnel-shaped flowers are 12 – long and 11 – across. They open at night. The spherical fruits are initially green and yellow when ripe.

Taxonomy
Strophocactus brasiliensis was first described, as Acanthocereus brasiliensis, by Britton and Rose in 1920. It was transferred to the genus Pseudoacanthocereus as Pseudoacanthocereus brasiliensis by Friedrich Ritter in 1979, a placement still accepted by some sources. A molecular phylogenetic study of the Hylocereeae by Korotkova et al. published in 2017 showed that Pseudoacanthocereus brasiliensis formed a clade with Strophocactus wittii and Pseudoacanthocereus sicariguensis (the only other species placed in Pseudoacanthocereus):

Accordingly, both species of Pseudoacanthocereus were transferred to Strophocactus.

Distribution and habitat
Strophocactus brasiliensis is native to Northeast and Southeast Brazil in the states of Bahia and Minas Gerais at altitudes of 40 to 700 meters. It is found in the eastern caatinga ecoregion, an area of thorn scrub and seasonally dry forests.