Synodontid catfish: a new group of weakly electric fish. Behavior and anatomy.

Three species of synodontid catfish can produce weak biphasic electric discharges in either continuous or burst-like fashion. The peak-power frequency of these electric organ discharges is around 100 Hz. The electric organ appears to have originated from a sonic muscle: the organ lies dorsal to the swim bladder, contains modified muscle tissue, and is innervated from a motor nucleus located in the caudal medulla. It is possible that synodontid catfish use electric signals in communication and/or object detection.