Cleistocactus smaragdiflorus

Cleistocactus smaragdiflorus is a species of Cleistocactus found in Bolivia and Argentina.

Description
Cleistocactus smaragdiflorus grows as a shrub with branched, arched to creeping shoots at the base and reaches heights of growth of up to 1 meter with a diameter of 2 to 3 centimeters. There are 12 to 14 low ribs present. The 4 to 6 yellowish or brown central spines are 1.5 to 3.5 inches long. The 10 to 34 radial spines that are up to 10 millimeters long.

The tubular, straight flowers are erect and 4 to 5 centimeters long. The flower tube is red to pink. The bracts are little spread. The stylus protrudes slightly from the flower. The spherical fruits reach a diameter of up to 1.5 centimeters.

Distribution
Cleistocactus smaragdiflorus is found in the Bolivian department of Tarija and the Argentine provinces of Jujuy, Salta, Tucumán and Catamarca at altitudes of 300 to 1500 meters.

Taxonomy
The first description as Cereus smaragdiflorus was in 1894 by Frédéric Albert Constantin Weber. Nathaniel Lord Britton and Joseph Nelson Rose placed them in the genus Cleistocactus in 1920. Other nomenclature synonyms are Cereus colubrinus var. smaragdiflorus F.A.C. Weber (1894), Cereus baumannii var. smaragdiflorus (F.A.C. Weber) K. Schum. (1897) and Cereus colubrinus var. smaragdiflorus (F.A.C. Weber) Rol.-Goss. (1904).

Cleistocactus smaragdiflorus is closely related to Cleistocactus ferrarii.

In the IUCN Red List of Threatened Species, the species is listed as "Least Concern (LC)".