In most electric fishes derivative of muscle fiber, specialised to release electric discharges without contraction of the cell-body. The voltage of a single electrocyte corresponds to that of a normal muscle fiber, i. e. about –100 mV. But by arranging many hundreds of electrocytes in series the voltage sums up to about 15-20 V (clamp voltage, i. e. out of the water which would short-circuit the electric current.) in weakly electric fishes. Because of the high conductivity of the water the pulses are attenuated to only about 2 V. (In contrast in the strong electric catfish, Malapterurus spp. of Africa and the South American electric eel, Electrophorus electricus, even in the ambient water many hundreds of volts may be measured.) In Mormyridae the electrocytes are flat, plate like, and indirectly innervated, i.e. by means of peculiar stalks which remind miniature mangrove roots. These stalks, one or more per cell, depending on the species, may either merge at the face of origin of the particular electrocyte, or they may even penetrate it before merging, again depending on the genus or species. The nerve endings (synapses) are positioned on the upper ends of the stalks. Because the non-innervated side of such a cell is electrically excitable, the discharges usually are biphasic, a negative phase being followed by a positive phase. Monophasic and triphasic discharges also may be produced, again depending on the species etc. Due to the arrangement of the electrocytes and/or the structure of the stalk(s), the polarity of an electric fish may either be head positive or head negative. In Gymnarchus the electrocytes are drum-shaped, innervated at the posterior end, its discharges are head positive.

Alternative forms for electric cell : electrocyte, electroplaque, electroplate, electroplax.