subspecies

[Norbert Hahn]

Within a purely hierarchical classification system the subspecific
delimitation of taxa could be considered clumsy and none describe especially
if on has at times to contend with quadnomes as in botany. Within a
phytogeographic context the subspecific classification of taxa does however
carry merit as it helps to give some indication to the interaction between
areas. Within the context of my studies pertaining to the Soutpansberg, a
region note for its immense biological diversity many patterns of floristic
integration can be shown through examples of subspecific taxa. As an example
the genus Dicrostachys is a widely distributed genus throughout Africa.
Within my region the  genus is represented by a single species, D. cinerea.
D. cinerea is again represented by two subspecies namely subsp. africana a
constitute of the dryer savanna regions of southern Africa and subsp.
nyassana a representative of the more tropical savanna constitute. D.
cinerea subsp. africana is split into three variats, var. africana and var.
pubersens these represent the busveld componets were var. lugardiae
represents the dry Kalaharie florisic elements. In my region all fore taxa
can be found sympatrically or in close proximity of one another. If one had
was to ignore the subspecific classification an immense amount of
phytogeographic information is lost. To try and move the various taxa to
specific level would pose and incredibly difficult task as these so called
forms show integration where the occur sympatrically.

I believe that one has to try and be realistic about the implementation of a
subspecific classification. We are still fare from understanding the
interaction of populations and the concepts pertaining to specietion. From a
field biologist point of view it is sometimes more realistic to have a taxa
spilt into subspecific rank than as a species.

Norbert Hahn
Director ICONS
P.O. Box 1734
Louis Trichardt
0920, South Africa
Tel: SA 015-5177176
E-mail: hahn1 at mweb.co.za