Reedfish

Description

The reedfish, ropefish (more commonly used in the United States), or snakefish, Erpetoichthys calabaricus, is a species of freshwater fish in the bichir family and order. It is the only member of the genus Erpetoichthys. It is native to West and Central Africa. The reedfish possesses a pair of lungs in addition to gills, allowing it to survive in very oxygen-poor water. It is threatened by habitat loss through palm oil plantations, other agriculture, deforestation, and urban development. The reedfish reaches a maximum total length of 37 cm (15 in). It has an eel-like, elongated body without a trace of a ventral fin. The long dorsal fin consist of a series of well-separated spines, each supporting one or several articulated rays and a membrane. The reedfish possesses a pair of lungs, enabling it to breathe atmospheric air. This allows the species to survive in water with low dissolved oxygen content and to survive for an intermediate amount of time out of water. Larvae have conspicuous external gills, making them resemble salamander larvae. The genus name derives from the Greek words erpeton (creeping thing) and ichthys (fish). The reedfish inhabits slow-moving or standing, brackish or fresh, warm water at temperatures of 22–28 °C (72–82 °F). It occurs in Benin, Cameroon, Nigeria and possibly the Republic of the Congo, spanning the area from the Ogun River to the Chiloango River. The reedfish is nocturnal, and feeds on annelid worms, crustaceans, and insects. When moving through water slowly, it tends to use its pectoral fins, changing to an eel-like form of swimming (making more use of full-body movements and the caudal fin) when moving quickly. Both in the wild and in captivity, reedfish are known to explore land if given the opportunity, slithering along like a snake and also taking food items on land. Females repeatedly deposit small batches of eggs between the anal fins of the male, where they are fertilized. The male reedfish then scatters the eggs among aquatic vegetation, where they stick to plants and substrate. Larvae hatch rapidly (after 70 hours) but remain attached to vegetation; they become independent and start to feed after 22 days, when the egg's yolk sac has been consumed. In coastal central Africa, the species is threatened by habitat loss, driven by the development of oil palm plantations. Populations in western Africa are impacted by degradation and loss of habitat from wetland drainage for agricultural and urban developments.