The classification of cacti has been an ever-changing task that
has consisted of a good deal of naming and renaming. This is due
in large part to the extremely variable growth habits of most cacti.
Many cacti plants of the same species may appear quite different
from one another. Cacti also reproduce proficiently through vegetative
means creating large numbers of a particular variation and therefore
furthering the impression that what is actually a variety is instead
a unique species.
Because of this, early publications written by both amateurs and
professionals that described and classified cacti created a lot
of confusion as to which names and groups were to be accepted and
which were not. Most classification was performed by individuals
up until 1984 when the International Cactaceae Systematics Group
was formed to standardize the classification of cacti.
Despite the efforts of the International Cactaceae Systematics
Group (ICSG), people today are still faced with inaccurate and/or
outdated information through many on-line and printed resources
as well as through word of mouth. This creates confusion for those
attempting to identify an individual cactus plant.
In classifying the species listed on Cactiguide.com, I have decided
to use Edward F. Anderson's book, The Cactus Family, whenever
possible. In this book he states,
"I would not pretend to work independently of the many specialists
and colleagues with whom I have been associated in this project
since 1984. Rather, I defer to the judgment of the International
Cactaceae Systematics Group and the classification system used in
this book is essentially that of the experts who make up the group."
Rather than my trying to duplicate his work, I have also used Anderson's
The Cactus Family to list the appropriate synonyms of each
species. I have not, however, listed the name of the person who
first described the plant as is the custom to do because it is not
necessary for identification.
Because many names that were rejected by the ICSG are still heavily
used today, I have listed the many synonyms for each species in
accordance with those listed in The Cactus Family.
NOTE: CactiGuide.com is intended as a source for the positive
identification of a particular cactus plant. For further study including
biological information, histories, conservation, and growing tips,
I strongly recommend other sources such
as The Cactus Family, which covers all of those subjects