Acanthocalycium

Acanthocalycium aurantiacum
Acanthocalycium ferrarii
Acanthocalycium glaucum
Acanthocalycium klimpelianum
Acanthocalycium peitscherianum
Acanthocalycium spiniflorum
Acanthocalycium violaceum
etc.

Acanthocalycium is a genus of cactus consisting of several species from Argentina. The taxon name comes from Greek akantha (meaning prickly) and kalyx (meaning buds), which refers to the spines on the floral tubes.^[1]

These plants are globose to elongate, with numerous ribs on the spiny stems. Flowers range from white to pink to red and open during the day.

Spinicalycium Fric (nom. inval.) has been brought into synonymy with this genus. Besides, the genus Acanthocalycium has been periodically included in the genus Echinopsis.

The flower of Acanthocalycium spiniflorum