CSA-Journal-2016-04

tracyanum. After reading a number of
taxonomic papers, it seems that subgeneric
rankings of subspecies or section have
been used variously for cymbidiums over
the years. The most recent is the section
arrangement used by Du Puy and Cribb in
the book, “The Genus Cymbidium”. We’ll
use that one here. All of these rules are laid
out by the International Association for
Plant Taxonomy.
What is a cymbidium? The definition
of the genus Cymbidium was published
in 1799 by Olof Peter Swartz in the journal
whose title is abbreviated: Nov Act Soc Sc
Upsal. Swartz was probably the first specialist
in orchid taxonomy and he studied
under Linnaeus the younger, whose father
established the binomial nomenclature we
use today. There are various descriptions of
the genus but one of the best is in the book
entitled “The Genus Cymbidium” by David
Du Puy and Phillip Cribb (see references).
The features that identify cymbidiums include
aspects of leaf anatomy, pseudobulb
structure and either two or four pollinia.
Under this careful definition of cymbidium,
how many actual species are there?
There are some places to look, especially
in web accessible databases. First, there is a
working list of all plant species, The Plant
List, created by Royal Botanic Gardens,
Kew and the Missouri Botanical Garden
and posted in the internet at http://www.
theplantlist.org/. These institutions gathered
all of the plant checklist datasets they
could find and generated a stupendous
master list. The new list combines a number
of already huge lists stretching from
the 200,000 names in the International
Organization of Plant Information to the
“Tropicos” information system of the Missouri
Botanical Garden which holds over
a million names and 3.9 million herbarium
specimens. They further examined all of
the names and rated those with sufficient
information as “Accepted”. The synonyms
and unresolved names are also included.
Fig. 1. Olof Peter Swartz (1760-1818).
The author of the genus description for
cymbidiums published in 1799
We therefore may count the cymbidium
information here as reasonably authoritative
and probably inclusive. The Plant List
returns 527 entries under the search term
Cymbidium. Of these, 92 were rated as
“Accepted”. Removing the subspecies and
varieties leaves 72 species. In contrast Du
Puy and Cribb in the 2007 book list 52 species.
The difference stems from several issues.
Some names have been assigned in
new reports published after the book. However,
Du Puy and Cribb examined hundreds
of plant specimens in herbaria around the
world as well as the literature and they resolved
a number of the ambiguous names.
If we combine the 52 well annotated ones
and the new species the total comes to 60
species (Table 1).
For ease of handling, the species are
arranged into sections. There are 11 sections
in the genus. If we exclude the six sections
with one or two species, the majority
are divided among four sections: Cymbidi-
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