Quote:

The simultaneous phylogenetic analysis of both morphological data and noncoding
DNA sequence data recovered Trichocereus as monophyletic if two species of Harrisia are part of it.

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Quote:

As a result of comparing the original description
with the presently known Trichocereus species, we
conclude that C. macrogonus Salm-Dyck is the same
species known as T. peruvianus, and that it is conspecific
with T. pachanoi but differentiable at a lower
(infraspecific) level.

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Quote:

The chloroplast DNA phylogeny presented
here for 144 species and subspecies representing all major
groups of Echinopsis sensu lato as well as all genera of Trichocereeae
demonstrates the polyphyly of this genus as currently circumscribed.
..
A new generic
classifi cation of the Trichocereeae now requires finding morphological
characters sufficiently conservative for distinguishing
larger groups of species. Seed morphology and growth
form, perhaps in combination, seem promising starting points.

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