Included here are the rainforests of the Atlantic coast of Africa from southwestern Gambia to eastern Ghana. They are confined to the highly humid southern and western areas where rainfall can exceed 4000 mm per year. They have an evergreen aspect throughout the year and only during a short period between November and January can a few deciduous trees be seen in the emergent and upper canopies. Three stories can usually be identified. The upper canopy, which often exceeds 30 m, typically includes Lophira alata, Parkia bicolor, Piptadenia africana, Terrietia utilis and endemic or near endemic species such as Cynometra ananta (Fabaceae), Coula edulis (Olacaceae), Daniellia thurifera, Gilbertiodendron preussi (Fabaceae), Dialium aubrevillei (Fabaceae), Drypetes aylmeri (Euphorbiaceae), Erythrophleum ivorensis (Fabaceae), Khaya ivorensis (Meliaceae), Scaphopetalum amoenum (Sterculiaceae) and Soyauxia grandifolia (Medusandraceae). The lower stories usually comprise Cola chlamydantha, Diospyros sanz-minika, Funtamia africana, Pentadesma butyracea, Protomegabaria stapfiana, Strombosia pustulata together with endemic species such as Allanblackia parviflora (Hypericaceae), Calpocalyx brevibracteatus (Fabaceae) and the ebony trees Diospyros cooperi, D. heudelotii and D. vignei (Ebenaceae). The shrub layer is often sparse but may include Bertiera racemosa, Heisteria parvifolia, Randia hispida and the endemic Mussaeada chippii (Rubiaceae). Likewise, herbaceous ground layer species are scarce but the sedge Scleria barteri may become extensive when the tree canopy is more open. Other herbaceous species include various pteridophytes such as Gleichenia linearis, Lygodium macrophyllum, Lycopodium cernuum and Selaginella myosurus. Among the many lianas and creepers are Alafia barteri, Baissea multiflora, Combretum comosum, Griffonia simplicifolia and Landolphia owariensis. The epiphytes are mainly pteridophytes such as Arthropteris orientalis, Dynaria laurentii, Microsorium punctatum and Platycerium angolense, or orchids such as Bulbophyllum ssp. These forests are also of considerable interest for the presence of the endemic Pitcairnia feliciana, the only Old World member of the American family Bromeliaceae, and Rhipsalis cassutha (Cactaceae), the only cactus found in the Old World.
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