Description
The pectoral fin disc of the common torpedo is almost circular in shape and about 1.3–1.4 times wider than long. The front margin of the disc is nearly straight. The two large, kidney-shaped electric organs are visible beneath the skin on either side of the head. The eyes are small and followed by spiracles of comparable size. The lateral and posterior rims of the spiracles bear small, low knobs, which diminish in size with age and may be indiscernible in larger individuals. On the "nape" behind the spiracles, there is a pair of prominent mucous pores. There is a wide, quadrangular flap of skin between the nostrils that almost reaches the mouth. The teeth are small and arranged in a dense quincunx pattern; each tooth has a single sharp cusp. There are around 22–24 and 20–22 tooth rows in the upper and lower jaws respectively. The five pairs of gill slits are placed on the underside of the disc.
The pelvic fins are distinct from the disc and have rounded outer margins. The short and thick tail bears skin folds along either side and two dorsal fins on top. The first dorsal fin is slightly larger than the second. The well-developed caudal fin is triangular with blunt corners, and is approximately as long as the space between it and first dorsal fin. The skin is smooth and soft, entirely lacking dermal denticles. The dorsal coloration of the common torpedo is light to dark brown, with distinctive large spots ("ocellae") on the disc; each ocellus is blue and encircled by darker and lighter rings. Typically there are five ocellae arranged symmetrically in a row of three and another of two; rays with 0–4 ocellae are less common, and those with more than five are rarer still. An unusual male with eight ocellae was caught off Tunisia, and another with nine off southern France. When present, the sixth ocellus is similarly sized to the first five and positioned at their center; any additional ocellae tend to be smaller than the first six and placed asymmetrically towards the snout. The underside is cream-colored, with dark disc margins. An adult albino female was captured off Tunisia. Males and females typically measure 30 and 39 cm (12 and 15 in) long respectively; the largest individual on record was 60 cm (24 in) long. Rays from off West Africa grow larger than those from the Mediterranean.
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