Electric catfish or Malapteruridae is a family of catfishes (order Siluriformes). This family includes two genera, Malapterurus and Paradoxoglanis, with 21 species.[1] Several species of this family have the ability to generate electricity, delivering a shock of up to 350 volts from its electric organ.[2] Electric catfish are found in tropical Africa and the Nile River. Electric catfish are usually nocturnal and carnivorous.[2] Some species feed primarily on other fish, incapacitating their prey with electric discharges,[2] but others are generalist bottom foragers, feeding on things like invertebrates, fish eggs, and detritus.[3] The largest can grow to about 1.2 meters (3 ft) long, but most species are far smaller.
The Malapteruridae are the only group of catfish with well-developed electrogenic organs; however, electroreceptive systems are widespread in catfishes. The electrogenic organ is derived from anterior body musculature and lines the body cavity.[4] Electric catfish do not have dorsal fins or fin spines. They have three pairs of barbels (the nasal pair is absent).[4] The swim bladder has elongate posterior chambers, two chambers in Malapterurus and three in Paradoxoglanis.[4]
Malapterurus have been conditioned by means of reward to discharge on signal. As reported in the New York Times, April 2, 1967, a researcher, Dr. Frank J. Mandriota of City College, New York, conditioned an M. electricus to discharge on a light signal for a reward of live worms delivered automatically. This is the first conditioning that modified neither glandular nor muscular responses.
The largest can grow to about 1.2 meters (3 ft) and .[2] [4] Most Malapterurus and all Paradoxoglanis species are much smaller, reaching less than long.[4]
The electric catfish of the Nile was well known to the ancient Egyptians.[5] The Egyptians reputedly used the electric shock from them when treating arthritis pain.[6] They would use only smaller fish, as a large fish may generate an electric shock from 300 to 400 volts. The Egyptians depicted the fish in their mural paintings and elsewhere;[5] the first known depiction of an electric catfish is on a slate palette of the predynastic Egyptian ruler Narmer about 3100 BC.[7] [8]
An account of its electric properties was given by an Arab physician Abd al-Latif al-Baghdadi of the 12th century; then as now, the fish was known by the suggestive name of Arabic: الرعد ''el raad''|italic=unset, which means "thunder".[5]
The shock of these catfish is used to stun prey and in defense. It is not known to be fatal to humans,[2] but large electric catfish can stun an adult person.[6] In small electric catfish, the generated current is far less and only feels like a tingle to humans.[6]