Trichocereus and Echinopsis are two genera of cacti that have been a subject of taxonomic debate and revision over the years. In 1909, Vincenzo Riccobono classified a group of columnar cacti under the genus name Trichocereus. These cacti were characterized by their tall, columnar growth habit and beautiful flowers.
However, in 1974, Friedrich Ritter reevaluated the classification and merged Trichocereus into the genus Echinopsis, along with another genus called Lobivia. This decision was based on a reassessment of the morphological and genetic characteristics of these cacti. The rationale behind this merger was to create a more coherent and simplified classification system for these closely related plants.
The decision to merge Trichocereus into Echinopsis was met with some controversy and not all cactus experts agreed with this reclassification. Some argued that Trichocereus should remain a distinct genus due to the unique characteristics exhibited by its members. Others supported the merger, considering the similarities between Trichocereus and Echinopsis to be significant enough to warrant the consolidation.
Personally, I have come across this taxonomic debate in my own gardening experiences. I have grown several cacti from the Trichocereus and Echinopsis genera, and while they do share some similarities in terms of appearance and growth habit, there are also subtle differences that make each genus unique.
One way to distinguish between Trichocereus and Echinopsis is by examining their flowers. Trichocereus cacti often produce large, showy flowers that bloom at night and have a strong fragrance. On the other hand, Echinopsis flowers tend to be smaller and may bloom during the day, with a milder scent.
Another distinguishing feature is the presence of spines. Trichocereus cacti typically have longer and thicker spines compared to Echinopsis, which often have shorter and more numerous spines. However, it’s important to note that there can be variation within each genus, and not all species will conform to these general characteristics.
In recent years, there has been a growing trend among cactus enthusiasts to revert to using Trichocereus as a separate genus. This is based on a reevaluation of the genetic and morphological data, as well as a desire to preserve the historical classification and the unique characteristics of Trichocereus cacti.
While Trichocereus was initially classified as a separate genus, it was later merged into Echinopsis by Friedrich Ritter in 1974. However, the taxonomic status of these genera remains a subject of debate among cactus experts. The decision to merge Trichocereus into Echinopsis was based on a reevaluation of their characteristics, but some argue for the reestablishment of Trichocereus as a distinct genus. Ultimately, the classification of these cacti continues to be an evolving field of study.
