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egion: high species concentrations are indeed
often restricted to specific locations. Most of these
areas are rich in endemics—plants that are confined
to specific areas. The Drakensberg Mountain
range in Lesotho and southeastern South Africa is
one such area. The vegetation of the area has been
classified differently by various scientists over the
years:
• Eastern Mountain Region (Phillips 1917)
Austro-afroalpine Region (Van Zinderen-
Bakker & Werger 1974)
Austral Domain of the Afroalpine Region
(Werger 1976, pers.comm. in Killick 1994)
Afro-alpine Region (Killick 1978)
Altimontane vegetation (White 1983)
South-eastern Mountain Regional Mosaic
(Hilliard & Burtt 1987)
Drakensberg Alpine Region (CPD Site Af82)
(Killick 1994)
Alti/Afro Mountain Grassland (Low & Rebelo
1996)
Vegetation
Broadly classified within the over-exploited
grassland biome (Rutherford & Westfall 1986), the
area was classified as Themeda-Festuca Alpine
Veld (veld type 58) by Acocks (1975). The area
consists essentially of species-rich subalpine
(1800–2800 m) grasslands dominated by Themeda
triandra, but with a wide variety of other
monocotyledons and dicotyledons. There are also
“patches of wet meadow and marshland at all
altitudes and small areas of dwarf shrub heaths on
steep and rocky ground” (Greyling & Huntley 1984).
According to Schwabe (1990), there are three
types of wetlands found within the SNPCtarns,
riparian marshes and inland freshwater marshes.
All are effective sediment traps and stabilisers of
stream flow because of their capacity to store
sediments and water. Tarns are depressions in the
sandstone that are filled with water and have very
little emergent vegetation associated with them. It
is in these tarns that the rare Aponogeton
ranunculiflorus, described in 1972, may be found
(Jacot Guillarmod & Marais 1972; Jacot
Guillarmod et al. 1973; Jacot Guillarmod 1977,
1978). The species flowers in January and has
been described by Zonneveld (1998) as the “jewel
SABONET News Vol. 4 No. 2 August 1999
of Sehlabathebe”. It was first discovered in the
tarns of SNP. Subsequently, specimens were noted
in tarns and pools along the Drakensberg escarpment,
but all at approximately the same altitude of
2 600 m. Its distributional range is restricted,
however, to less than 10 km (Jacot Guillarmod
1977, 1978). It has been listed as rare mainly
because the habitat is so readily disturbed—
erosion causes silting of the water which cuts out
the light necessary for photosynthesis and subsequent
growth of the plant (Jacot Guillarmod et al.
1973). Within SNP, A. ranunculiflorus is found
solely in the tarns in the eastern and southern parts
of the park. The flower head is borne at the top of
a long, slender peduncle, and the open inflorescence
resembles a white buttercup floating on the
water—hence the specific epithet ranunculiflorus.
The leaves seldom reach 10 cm in length and are
always under water: the clear pools, however,
allow enough light to penetrate to allow photosynthesis
to take place (Jacot Guillarmod 1977). It
grows readily in cultivation (Jacot Guillarmod
1978).
Herbarium
The 1970s was a decade of much activity in SNP,
due largely to the efforts of Amy Jacot Guillarmod
and three US Peace Corps volunteers whose names
are intimately associated with the plants of SNP—
Alan C. Beverly, Fred K. Hoener and M.K.
Rutledge. Alan Beverly was the Associate Botanist
in SNP from December 1975 to July 1977,
whilst Fred Hoener was the Botanist from February
1976 to September 1979 (Gunn & Codd 1981).
Fred Hoener was responsible for compiling a
checklist of the flora in SNP during 1979.
Whilst working in SNP, the US Peace Corps
volunteers established an herbarium (Sehlabathebe
National Park Herbarium) which is housed in the
Research Centre, close to the park’s main gate (see
also Smith & Willis 1999a,b). This is probably the
only A-framed building housing an herbarium in
southern Africa. During their time in SNP, Hoener,
Beverly and Rutledge managed to mount and
deposit in the herbarium ca 950 specimens, representing
238 genera and 469 species. The identification
of most of the specimens were confirmed or
determined by staff of the National Herbarium
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