Included here is the forests of southwestern Dahomey, southern Nigeria, western Cameroon, Equatorial Guinea, most of Gaban and western Congo. They are often characterized by species of the Fabaceae sub-family Caesalpinioideae and species such as the endemic Calpocalyx heitzii (Fabaceae – sub-family Mimosoideae) and the regional endemic Sacoglottis gabonensis (Humiriaceae). They are more or less arranged in three strata. Large emergents and upper canopy trees reach heights of 35-50 m and include many regional endemics such as Anthonotha fragrans, Aphanocalyx margininervatus, Erythrophleum ivorensis (Caesalpinioideae), Desbordesia glaucescens (Irvingiaceae), Lovoa trichilioides (Meliaceae) and Pterocarpus soyauxii (Fabaceae). The sub-canopy at heights ranging from 20-35 m is often dominated by the endemic Calpocalyx dinklagei (Fabaceae) and regional endemics like Dialium pachyphyllum, Tetraberlinia bifoliofolia (Caesalpinioideae), Dichostemma glaucescens (Euphorbiaceae), Diogoa zenkeri, Strombosia grandifolia (Olacaceae), Greenwayodendron suaveolens (Annonaceae) and Santira trimera (Burseraceae). The under storey tends to be discontinuous and reaches about 10 m in height. Typical small trees and shrubs include endemic s like Allexis cauliflora, Rinorea albidiflora (Violaceae), Asystasia macrophylla (Acanthaceae), Crotonogyne manniana (Euphorbiaceae), Palisota ambigua (Commelinaceae) and Scaphopetalum blackii (Sterculiaceae), together with many regionally endemic species such as Diospyros preusii (Ebenaceae), Jollydora duparquetiana (Connaraceae) and Massularia acuminata (Rubiaceae). The ground flora is largely dominated by seedlings, but also includes many herbaceous species such as the endemic grass Puella schumanniana (Poaceae).

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