Species
Knuthianus
A published name with a small field record behind it, doing service in the trade for more than one plant.
The name
The International Plant Names Index records Trichocereus knuthianus Backeb. as a validly published name, first published in 1937. The current treatment does not keep it as a species of its own: it is carried in the synonymy of Trichocereus cuzcoensis.Reported by one source, and not corroborated anywhere else.
What has been found in the wild
Asked for Trichocereus knuthianus by name, the collectors' own field-number lists return 3 distinct collections from 2 collectors, one of them on the Rio Maranon in Peru.Reported by one source, and not corroborated anywhere else.
What the name covers
A licensed Californian nursery sells at least two distinct plants under this name, from different countries and from different growers, and compares one of them against a third.Too little stands behind this for us to confirm it.
What that means when you buy one
A plant labelled knuthianus tells you which epithet the seller reached for. On its own it does not tell you which plant you are getting.
What growers report
One grower describes a knobbly profile, and a strain in their own collection carrying unusually long spines of the kind you would expect on a bridgesii.Reported, but not confirmed.
Names in the library filed under this species
These are entries where a source names this species for the plant. An entry is not listed here because its name looks like the epithet — that would be a guess, and a guess is what this library exists not to publish.
Every feature on this page moves with age, sun and water: a thirsty plant in hard light grows longer spines and a heavier bloom than the same clone in the shade. None of it settles an identity on its own, a clone name is not proof of a species, and a photograph is a pointer rather than an answer.