An area of approximately 102'700 suqare kilometers, with 5'000 higher plant species of which nearly 40% are endemic. It has the richest succulent flora in the world; about one-third of the world’s approximately 10'000 succulent species. Miniature succulents (435 spp.) and geophytes (630 spp.) are also unique to this ecoregion. About 18% species are threatened. Vegetation of this area consists of low, succulent-leaved shrubs, few grasses, and a scarcity of tall shrubs and trees.
The region stretches southward down the western coast of Namibia from the town of Luderitz into South Africa. Nama Karoo lies on the east of this region. Lowland and Montane Fynbos and Renosterveld ecoregions are south of this region.
There are two zones:
This is a fog-affected coastal plain and adjacent escarpment in the west which receives winter rains. It is made up of the following subregions:
|Sperrgebiet||Luderitz , Southern Namibia|
|Richtersveld||Desert mountain region adjacent to the Orange River||Northwest of Vioolsdrif and north-east of Alexander Bay|
|Sandveld||Sandy coastal plain||South of the Olifants River: south of Lamberts Bay; north of Velddrif|
|Hardveld||Granitic uplands of the Great Escarpment||West of Bitterfontein; north of Lutzville, Koekenaap|
|Kamiesberg||Granite massif of 1'800 m along the escarpment||East of Kamieskroon, Garies; west of Platbakkies.|
|Knersvlakte||Quartz-strewn plains in the extreme south of the region||North of Bokkeveld; east of Bitterfontein; north-west of Hantam (Clanwilliam)|
This subregion lies east of the Namaqualand-Namib Domain, is not subject to fog, and receives most of its rain in spring and autumn. It is made up of the following subregions:
|Western Mountain Karoo||Southwestern sector of the Great Escarpment|
|Tanqua Karoo||Large, arid basin located between the Western Mountain Karoo and the fynbos-clad Cape Fold Mountains||West of Roggeveld mountains; east of Ceder Mountains|
|Little Karoo||Basin to the southeast, surrounded entirely by Cape Fold Mountains|
There are three perennial river systems in the Succulent Karoo originating west in wet mountain areas. In earlier days elephants (Loxodonta africana), black rhinoceroses (Diceros bicornis) and hippos (Hippopotamus amphibius) were found in these areas.
The Gariep River is the longest perennial river in South Africa and originates in the highlands of Lesotho. It is the main source of water for the Sperregebiet.
Olifants River originates in the fynbos covered Cape Fold Mountains. So does its tributary, the Doring River.
The Olifant-Gourits-Groot River System runs through the Little Karoo. Its water comes from the adjacent Cape Fold Mountains.
102'700 square kilometers
Nature Reserves found in this ecoregion are:
|Sperregebiet||Protected Diamond Area of 26'000 square kilometers, which can be entered only by permit. This area has been sealed off from public access since 1910.|
|Namaqua National Park||500 km square kilometers||Southwest of Springbok, west of Kamieskroon; northeast of Hondeklipbaai|
|Knersvlakte Nature Reserve||74 km square kilometers; Namaqualand-Namib Domain|
|Anysberg Nature Reserve||South of Matjiesfontein|
|Groenefontein Nature Reserve||47 km square kilometers|
|Richtersveld National Park||Northwest of Vioolsdrif and north-east of Alexander Bay|
|Goegab Nature Reserve||Springbok|
|Vrolikheid Nature Reserve||The landscape is rugged and strikingly scenic, with sandstone and underlying shale formations. The vegetation of this rocky part of the Little Karoo is known as arid Robertson Karoo.||15 km south of Robertson on the McGregor road|
Climate is mild compared to other arid areas. Succulent Karoo is thus unique among world's desert areas as rain is fairly predictable. Frost is extremely rare. Heavy dewfalls and fog accompany rain. Some of the hottest days (up to 40°C) occur in winter as a result of hot "berg" or mountain winds. Namib Desert in the north receives less than 50 mm summer rain per year. The cold Benguela Current of the Atlantic Ocean generates fog, which cools down summer heat. The hottest days in the coastal areas are actually in winter, due to hot winds from the interior mountains. Temperatures greater than 40°C are recorded in winter. The inland Southern Karoo Domain regularly experiences summer temperatures higher than 40°C.
Some succulents thrive in particular areas due to geomorphological features.
The region is host to 5'000 higher plant species, about half of the world's 10'000 succulent species. The region is dominated by succulents with little grass and a scarcity of tall shrubs and trees. About 67 genera and 1,940 species are endemic to this ecoregion.
The annual natural spring flower show comprises only about 8% of the area's flora, with very few endemic species. There are 390 species of annuals. About 1,700 species are leaf succulents, of which 700 are stone plants and their allies (Conophytum, Lithops etc.). The area is not rich in trees with only 35 species, but some trees are really strange looking: bastard quiver tree (Aloe pillansii), quiver tree (Aloe dichotoma), and halfmens (Pachypodium namaquanum).
There are 35 species of trees with 3 endemics
Some succulent genera have quite a large number of species:
The region is rich in bulb succulents, with 630 species of geophytes that are petaloid monocots in the families:
The coastal region has 29 species of lichens and 41 species of higher plants.
In the Kamiesberg area there are 86 endemics.
In the Knersvlakte (Vanrhynsdorp) area there are 150 endemic species, mostly dwarf succulents and geophytes.
The Little Karoo contains between 200 to 300 endemic species, mostly Mesembryanthemaceae. Genera include
The region contains 1,700 species of leaf succulents, 700 of which are stone plants and their allies (Conophytum, Lithops etc.).
Some succulent genera have many species:
There are 630 species of geophytes, most of which are petaloid monocots in the following families:
Vegetation is divided into categories according to subregions in which they occur. The three main regions are
The vygieveld (i.e. field of succulents) is the most widespread vegetation type. It contains dwarf to low shrubland ranging from less than 25 cm to less than 50 cm high. It is dominated by leaf succulents, particularly Crassula spp. and members of the Mesembryanthemaceae family (known in the vernacular as the vygie family).
The vygieveld is divided into the following subregions:
The Strandveld is open shrubland of 0.5 m to 2.0 m high. It covers the coastal plain of the Namaqualand-Namib Domain on deep sands of marine origin.
In autumn: amaryllid bulbs of Brunsvigia and Haemanthus show off brilliant blooms.
In spring: ephemerals flower.
The Broken Veld is found on rocky terrain in the escarpment zone of the Namaqualand-Namib Domain. It is the predominant vegetation of the Little Karoo. Its name refers to the scattered individuals of tall shrubs and small trees (2 m to 3 m in height) that "break" the uniformity of the low shrub layer, which is rich in succulents.
Renosterveld grows in the highlands of the Hardeveld, Little Karoo, Richtersveld, and the Western Mountain Karoo. Rainfall varies from 250 mm to more than 400 mm per year. This is a dense and taller shrubland.
Fynbos is found on infertile, wind-blown sands along the coast, as well as in the highest and wettest reaches of the Kamieberg.
Low perennial shrubs that bear succulent leaves, branches and stems dominate this area.
Long-tongued flies have tongues 50 mm long and are the exclusive pollinators of 28 species of Geraniaceae and Iridaceae in the Namaqualand-Namib Domain.
The region has 78 mammal species with 7 endemic species.
The region has 226 species of birds with 5 endemic species.
15 amphibians are found in this ecoregion
There are 115 reptile species: 48 are endemic and 15 are strict endemics.
Monkey beetles (Rutelinae: Hoplini) are largely endemic to southern Africa, and are concentrated in the Succulent Karoo.
Other bugs are