Jordaaniella dubia (Haw.) H.E.K.Hartmann
Jordaaniella anemoniflora (L.Bolus) Van Jaarsv. [ = Cephalophyllum
anemoniflorum (L.Bolus) N.E.Br. (Van Jaarsveld 2001)]
Family: Mesembryanthemaceae (Aizoaceae)
Common names: helder kruipvygie, matvygie (Afr.)

These two very attractive mesembs, one of which is widespread and
the other extinct in its natural habitat, can be grown in sunny
coastal gardens as they are perfect water-wise plants for such an
environment.
Description
Perennial,
creeping succulents with succulent leaves and large, solitary flowers.
J. anemoniflora has large white to pink flowers and linear
glaucous leaves. In contrast, J. dubia is a slightly smaller
species with club-shaped leaves and yellow flowers. Both species
have characteristic, many-chambered fruit with seeds that are dispersed
by rain.
Distribution and Habitat
The rare and distinct J. anemoniflora used to occur in openings
in Dune Thicket (Low & Rebelo 1996) (Strandveld), on the light
orange, coastal sandy flats between Macassar and Strand, near Cape
Town. The more widespread J. dubia is known from white sands
in Dune Thicket along the coastal strip from Hermanus to Lambert's
Bay. A third species, J. maritima (L.Bolus) Van Jaarsv.[
= Cephalophyllum maritimum (L.Bolus) Schwantes (Van Jaarsveld
2001)], occurs further east to Still Bay. It is the smallest of
the species and is variable in flower colour, and although the majority
have purplish flowers, orange and yellow-flowering forms also occur
(Van Jaarsveld 2001).
Derivation of name and historical aspects
The genus Jordaaniella was named for Professor Pieter Gerhardus
Jordaan (1913-1987), Professor of Botany at the University of Stellenbosch
(Smith et al. 1998) in 1984, by a world-renowned mesemb botanist,
Dr H.E.K. (Hartmann with four species, one of which was J.dubia
. However, three species previously included in the concept
of J. dubia are now recognised as distinct; J.dubia ,
J.anemoniflora and J.maritima. (van Jaarsveld (2001).
Anemoniflora indicates that the flower resembles an anemone
and dubia means doubtful, not confirming to type.
In 1992, the last natural population of J. anemoniflora was
removed from its habitat when it was bulldozed to make way for urban
expansion at Macassar, west of the Strand (Van Jaarsveld 2001).
Fortunately, the threatened plants were successfully re-introduced
into natural Dune Thicket vegetation at the military base northwest
of Macassar (Van Jaarsveld 2001).
Ecology
Flower colour polymorphism (species that have different-coloured
flowers) can have survival value when pollinators are scarce. In
Namaqualand, species of Dorotheanthus bellidiformis (bokbaaivygie)
may have several different colour morphs dominating. This may depend
on rainfall, and other ecological factors that may influence pollinator
number. Small flying insects such as bees, butterflies and moths
pollinate mesemb flowers. In the case of Jordaaniella, the
species were probably thought to be different-coloured populations
of the same species. However, J. anemoniflora and J. dubia
have been growing together in cultivation for years and are
known not to hybridize. This lack of crossing supports their status
as a distinct species.
Conservation
Future conservation of this species in the wild will depend upon
the maintenance of the newly developed City of Cape Town Biodiversity
Network (City of Cape Town 2003). Macassar forms a key part of the
network and has been recommended for conservation in a recent management
plan (Chittenden Nicks De Villiers 2002).
Uses and cultural aspects
Although some mesemb species have medicinal uses e.g. Carpobrotus,
none are known for species of Jordaaniella. Its main use
is in its attractive flowers and ease of growth for groundcover
in sandy gardens, particularly along the coast of the winter rainfall
region of South Africa.
Growing Jordaaniella dubia and J. anemoniflora
The species of Jordaaniella discussed above thrive in sandy
places. They are extremely easy to cultivate and can be grown from
cuttings or from seed. It is sufficient to just simply plant the
cuttings, with autumn being the best time (after the first rains).
No additional watering or nutrients are required. They are most
satisfying at flowering time between July and September when they
make an impressive and colourful addition to a water-wise coastal
garden.
References and further reading
- Chittenden Nicks de Villiers. 2002. Macassar Dunes Management
Plan (2001). Chittenden Nicks de Villiers, Cape Town.
- City of Cape Town. 2003. Biodiversity Network. City of
Cape Town, Cape Town.
- Goldblatt, P. & Manning, J. 2000. Wild flowers of the
fairest Cape. Red Roof Design in association with the National
Botanical Institute, Cape Town.
- Hartmann, H.E.K. 1984. Monographien der Subtribus Leipoldtiinae
6. Monographie der Gattung Jordaaniella (Mesembryanthemaceae).
Botanische Jahrbücher 104: 321-360.
- Hartmann, H.E.K. 2001. Illustrated handbook of succulent
plants. Aizoaceae F-Z. Springer-Verlag, Berlin.
- Low, A.B. & Rebelo, A.G. (eds). 1996. Vegetation of South
Africa, Lesotho and Swaziland. Department of Environmental
Affairs and Tourism, Pretoria.
- Manning, J. & Goldblatt, P. 1996. West Coast. South African
Wild Flower Guide 7. Botanical Society of South Africa, Cape
Town.
- Smith, G.F., Chesselet, P., Van Jaarsveld, E.J., Hartmann, H.,
Hammer, S., Van Wyk, B-E., Burgoyne, P., Klak, C. & Kurzweil,
H. 1998. Mesembs of the world. Briza Publications, Pretoria.
- Van Jaarsveld, E.J. 2001. South African succulent plants: two
new species and two new combinations. Haseltonia 8: 37-41.
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Author
Pascale Chesselet
Compton Herbarium Kirstenbosch
and
Barrie Low
Coastec, Rondebosch
July 2004
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