Echinopsis chamaecereus is a species of cactus from Argentina. Synonyms include Chamaecereus silvestrii and Lobivia silvestrii. It has been called the "peanut cactus", although other authors use this name only for Echinopsis silvestrii, a different species. E. chamaecereus has long stems about 1 cm (0.4 in) across. Orange flowers up to 4 cm (1.6 in) wide appear in late spring. In cultivation, E. chamaecereus is hardy to temperatures as low as −7 °C (19 °F) if kept dry.