Boundaries

The ecoregion is defined by the extent of the Malebo Pool of the Congo River, located directly north of Kinshasa. A largely lentic-adapted fauna inhabits the pool that spans the border of the Republic of Congo and the Democratic Republic of Congo.

Topography

According to the Cahen hypothesis, reported by Roberts and Stewart (1976)(Roberts and Stewart 1976), the Congo Basin is thought to have been an interior drainage throughout the Miocene and most of Pliocene, perhaps forming an interior lake. Then, in the late Pliocene or early Pleistocene, a Lower Guinean coastal river captured the Malebo Pool and the Congo Basin drained to the coast. 

Freshwater habitats

Many small islands are located within Malebo Pool; the largest is called Ile Mbamou and it divides the mainstream into two channels. Extensive palm and papyrus swamps occur along its edges and there is frequent passage of floating mats of Eichhornia (Bailey 1986). Malebo Pool experiences two flooding events due to its location at the equator and the flooding of northern and southern tributaries of the Congo River at different times of the year. The first and smaller flood occurs from April to June and the second, larger one from October to January. The average annual flow of the Congo River at Pool Malebo is 30,000 m³/s during the low water period and 60,000 m³/s during the flooding season. In 1961 and 1962, when there were heavy rains in the basin, the flow reached 80,000 m³/s.

Description of endemic fishes

Most endemic fishes are catfishes, with four endemic Amphiliidae, one Clariidae, and three Mochokidae, although several of these are known only from their type locality. Among endemic fish are the mountain catfish, Leptoglanis mandevillei, L. brieni, and L. bouilloni and an upside-down catfish, Atopochilus chabanaudi.

Justification for delineation

This ecoregion is defined by the extent of Malebo Pool directly above Kinshasa. A largely lentic-adapted freshwater fauna inhabits the pool.

Level of taxonomic exploration

Poor. Available data on the aquatic fauna of this ecoregion are old. Poll (1939; 1959) (Poll 1959)has published on the ichthyological fauna of the Malebo Pool and Sita (1980)(Sita 1980) has made a study of the vegetation. However, since those studies, there have been few studies on the aquatic flora and fauna reported from this ecoregion.