Echinopsis
Echinopsis is a genus of cacti native to South America, sometimes known as hedgehog cactus, sea-urchin cactus or Easter lily cactus., Plants of [the World Online] used a broad circumscription of the genus, resulting in about 80 accepted species, ranging from large and treelike types to small globose cacti. The name derives from echinos hedgehog or sea urchin, and opsis appearance, a reference to these plants' dense coverings of spines.
They are remarkable for the great size, length of tube, and beauty of their flowers, borne upon generally small and dumpy stems.
Taxonomy
Studies in the 1970s and 1980s resulted in several formerly separate genera being absorbed into Echinopsis. When very broadly circumscribed, Echinopsis sensu lato included over 100 species. Some genera have been absorbed and then accepted again. For example, the genus name Trichocereus was given to a number of columnar cacti in 1909 by Vincenzo Riccobono. The genus was subsumed into Echinopsis in 1974 by Friedrich, along with Lobivia. In 2011, it was argued that Trichocereus was distinct from Echinopsis, and a 2012 genetic and morphological study by Albesiano found Trichocereus to be monophyletic if it included three species of Harrisia.A 2012 genetic analysis of chloroplast DNA indicated Echinopsis was made up of several divergent lineages. This was shown again in 2019. It was concluded that previous taxonomic confusion was due to convergent evolution: species in different lineages had evolved to have similar growth and/or to share pollinators.
, Plants of the [World Online] subsumed Soehrensia, Chamaecereus, Trichocereus, and Lobivia into Echinopsis, resulting in a genus of around 80 species.
Species
Species of Echinopsis accepted by Plants of the World Online as of 2025:In addition, many hybrids exist, mostly between similar species, such as the cross between Echinopsis pachanoi and E. eyriesii which was sold under the name "Trichopsis pachaniesii" by Sacred Succulents.