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. In addition, many hybrids exist, mostly between similar species, such as the cross between
Echinopsis pachanoi (formerly
Trichocereus macrogonus var.
pachanoi) and
E. eyriesii (now
E. oxygona) which was sold under the name "Trichopsis pachaniesii" by Sacred Succulents. ==Distribution==