Included here are the mountains of the Congo Basin.

Congolian Montane Grassland

Natural or semi-natural mountain grasslands occur at altitudes ranging from 1900-2050 m in upland areas such as Mwanenguba and Mount Kupe. In the former they can be found girdling the shoulders of the Caldera, while on Kupe they often cap inselbergs embedded in the mountain. However, there appears to be no grassland species common to these two areas. On Mwanenguba the dominant grass is Sporobolus africanus, which occurs with a thin scattering of other species. Several of these, such as Cyanotis barbata, Habenaria peristyloides, Lactuca inermis and Nephrolepis undulata are perennials with underground rootstocks. However, most of the species are annuals that disappear during the dry season. These include Antherotoma naudinii, Conyza pyrrhopapa, Crotalaria subcapitata, Desmodium uncinatum, Galinsoga parviflora, Galium simense, Indigofera mimosoides, Lactuca inermis, Linum volkensii, Neontonia wrightii, Polygala palmata, Sebaea brachyphylla, Spermococe pusilla and the endemic Wahlenbergia ramosissima (Campanulaceae). On Kupe the dominant grass is Panicum hochstetteri. The only other common species is Gladiolus aequinoctialis. Less common species are Lobelia hartlaubii, Loudetiopsis trigemina, Monocymbium ceresiiforme, Plectranthus decumbens and the endemic Peucedanum kupensis (Apiaceae).

Congolian Crater Lakes

Crater lakes occur throughout the Cameroon Highlands. Lake Nyos in the Bamenda Highlands is probably the best known mainly because it released a cloud of poisonous gas in 1986 causing a number of fatalities. However, one of the best studied is Lake Edib but it is far from typical. A mattress of Sphagnum planifolium largely covers the surface water. On top of this is a distinct zonation of vascular plants. In the zone adjacent to open water species such as Cyperus pectinatus, Elaeocharis variegata, Oplismenus hirtellus and Pneumatopteris afra predominate. Moving landward a more species-rich zone occurs with species like Drosera madagascariensis, Habenaria weileriana, Laurembergia tetrandra, Ludwigia abyssinica, Pseudolycopodiella affine, Senecio ruwenzoriensis and Satyrium crassicaule. Another unexpected feature of this zone are prostrate climbers such as Secamone recemosa and Urera trinervis and obligate epiphytes like Begonia ampla and the endemic Impatiens letouzeyi (Balsaminaceae). There are several other clearly defined zones culminating in a belt of lake margin species with Cynorkis anacamptoides, Eulophia horsfallii, Floscopa glomerata, Habenaria procera, Polygonum setosulum, Rhynchospora corymbosa, Schoenoplectus mucronatus and the endemic fern Athyrium ammifolium (Woodsiaceae).

References

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Cheek, M., Pollard, B. J., Darbyshire, I., Onana, J. M. & Wild, C. 2004. The Plants of Kupe, Mwanenguba and the Bakossi Mountains, Cameroon. A Conservation Checklist. Royal Botanic Gardens, Kew.

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Morton, J. K. 1986. Montane Vegetation. In: Plant Ecology in West Africa. Ed. G. W. Lawson. John Wiley & Sons Ltd.

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