A round marbled disc lying buried in sand with two eyes on top, no barb on the tail, and a pair of organs behind the eyes that can deliver a shock of around 200 volts.
The organs are modified muscle. Thousands of flattened cells are stacked like the cells of a battery, each contributing a fraction of a volt, and the whole column fires at once when a nerve signal arrives. The ray uses it twice over: a heavy discharge to stun prey, which it then wraps in its disc and moves to its mouth, and a lighter one as defense.
A shock is not dangerous to a healthy adult, but it is entirely capable of knocking someone off their feet in shallow water, which is where the danger lies. The animal is buried, invisible, and does not move away - injuries are from standing on one.
This is also the fish that gave medicine its first electrical device. Roman physicians treated headache and gout by having patients stand on a live torpedo ray, and the effect was real enough that the practice ran for centuries. The word torpedo, for the numbness it produces, is older than the weapon.
How to recognise it
round flat disc, marbled brown on cream, with a short thick tail
two dorsal fins and a paddle-shaped tail fin, unlike a stingray
no tail spine at all
usually buried, with only the eyes and spiracles showing
This species is not commercially fished, but it is taken as bycatch in demersal trawl fisheries, coastal trammel nets and bottom longlines and often discarded at sea due to its low commercial value (Minervini et al. 1985). As a result of this discarding and the grouping of landings data with other rays, little information is available on the catch of this species. Fishing pressure from demersal trawl fisheries is relatively intensive on the continental shelf off western Africa.
Threat classification from the IUCN Red List.
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